EDCO 735 LIBERTY UNIVERSITY Statistics paper 1 Questions review_2024.pdf

Statistics paper 1 Questions

Q1.



The back-to-back stem and leaf diagram gives information about the ages of a random sample of

members of parliament in Canada and in the UK.

(a)Give a reason to support the use of a back-to-back stem and leaf diagram to represent this

information.

.............................................................................................................................................

(1)

Some information about the quartiles of these two distributions is given in the table below.

(b)Find the value of a, the value of b and the value of c

a = ...........................................................

b = ...........................................................

c = ...........................................................

(3)

(c)Write down the proportion of members of parliament in the UK that are likely to be older than 54 years

old.

Give a reason for your answer.

.............................................................................................................................................

(1)

(d)Compare the spread of ages for members of parliament in Canada with the spread of ages for

members of parliament in the UK.

State clearly the values of the statistic you use to make your comparison.

Interpret your comparison.

.............................................................................................................................................

(3)

One member of parliament in the UK wants to investigate the ages of the people living in her

constituency.

She suggests using the electoral register as a sample frame for her investigation.

(e)State one use of a sample frame in an investigation.

.............................................................................................................................................

(1)

(f)Assess the suitability of using the electoral register as a sample frame for this investigation.

.............................................................................................................................................

(2)



(Total for question = 11 marks)



Q2.



Laura owns a company that makes and sells packets of crisps.

Laura wants to find out how sales of different flavours of crisps have changed over the past five years.

Here is part of a spreadsheet showing information about the percentage of total sales for each flavour

sold by the company for each year from 2013 to 2017

(a)Explain one way that Laura can use the spreadsheet to check whether any of the data needs to be

cleaned.

.............................................................................................................................................

(1)

(b)Circle the cell in the spreadsheet that needs to be cleaned.

Write down what you think the correct value should be.

........................................................... %

(1)

Laura thinks that the company should stop making one of their flavours of crisps.

Laura notes that there is a downward trend in the percentage of total sales of ready salted crisps.

She also notes that there is a decrease of 1.8% between 2013 and 2017 and that this is greater than the

decrease for any other flavour.

One of Laura's employees, Ben, concludes that this means that it might be a good idea to stop making

ready salted crisps.

(c)Assess the validity of Ben's conclusion.

.............................................................................................................................................

(2)

Laura wants to do some quality control work to check the weights of large packets of crisps.

A sample of 10 large packets of crisps is taken at regular intervals and the mean weight of the packets in

each sample is calculated.

The sample means should be normally distributed with a mean of 510 g and a standard deviation of 20 g.

Laura is going to draw a quality control chart for the sample means.

The next two sample means are 495 g and 558 g.

(d)Explain how Laura should draw this quality control chart for the sample means and write down what

actions, if any, should be taken based on these two sample means.

.............................................................................................................................................

(5)

(e)Chose the correct words from the table below to complete correctly the following sentences.

(i)The population mean weight of large packets of crisps

should be .................................................................................................................... 510 g.

(1)

(ii)The population standard deviation of large packets of crisps

should be .................................................................................................................... 20 g.

(1)



(Total for question = 11 marks)



Q3.



The cumulative frequency diagram shows some information about the heights, in metres, of a random

sample of 50 of the tallest roller coasters in the world.

(a)Write down the number of roller coasters with a height of 80 metres or less.

...........................................................

(1)

(b)Work out an estimate of the number of these roller coasters with a height between 60 metres and 110

metres.

...........................................................

(2)

A safety company is going to inspect roller coasters with a height greater than 86 metres.

(c)Calculate an estimate of the percentage of the 50 roller coasters that the safety company is going to

inspect.

........................................................... %

(3)



(Total for question = 6 marks)



Q4.



The table shows information about houses for sale in Oxford.

An estate agent says the mode of the number of bedrooms for these houses is 3

(a) Explain how she knows this.

.............................................................................................................................................

(1)

The estate agent wants to investigate the prices of these houses.

She takes a stratified sample of 60 houses according to the number of bedrooms.

(b) Work out the number of houses in her sample for each number of bedrooms.

(3)

(c) Describe how to select the 60 houses in the sample.

.............................................................................................................................................

(3)



(Total for question = 7 marks)



Q5.



The population pyramid shows information about the numbers (in thousands) of drivers of each gender

who made car insurance claims in the UK in 2015

(a)How many female drivers aged 50–59 in the UK in 2015 made car insurance claims?

........................................................... thousand

(1)

The population pyramid shows that the age group which has the fewest number of drivers who made car

insurance claims is the 17–19 age group.

(b)Suggest a reason why this should be so.

.............................................................................................................................................

(1)

In 2014, the number of male drivers aged 20–49 in the UK who made car insurance claims was 66 700

(c)Compare the number of male drivers aged 20–49 in the UK who made car insurance claims in 2014

with the number of male drivers aged 20–49 in the UK who made car insurance claims in 2015

You must show your working.

.............................................................................................................................................

(3)

The SafeDrive insurance company charges young male drivers more for car insurance than it charges all

other drivers.

(d)Explain two features of the population pyramid which SafeDrive might use as its justification for doing

this.

.............................................................................................................................................

(2)

Jeremy says,

"The population pyramid shows that the total number of male drivers in the UK in 2015 is greater

than the total number of female drivers in the UK in 2015"

(e)Explain whether or not Jeremy's conclusion is appropriate.

.............................................................................................................................................

(1)

Vicki says,

"In the UK in 2019, there will be more male drivers who make car insurance claims than female

drivers who make car insurance claims"

(f)Explain whether or not the information in the population pyramid can be used to support Vicki's

statement.

.............................................................................................................................................

(1)



(Total for question = 9 marks)



Q6.



The table shows a summary of the results of a long jump competition.

(a)Find an estimate of the mean distance jumped.

You may use the extra columns in the table.

........................................................... m

(3)

(b)Draw a frequency polygon for the data.

(3)

(c)Describe any skew shown by the data.

.............................................................................................................................................

(1)



(Total for question = 7 marks)



Q7.



A farmer recorded the birth weights, in kg, of a sample of 50 piglets born on his farm.

The grouped frequency table gives information about his results.

Using the information in the table and the values of w as the class midpoints, the farmer finds that an

estimate for the mean birth weight of these piglets is 2.29 kg.

He also finds that

(a)Show that an estimate of the standard deviation of the birth weights of these 50 piglets is 0.7 kg,

correct to 1 decimal place.

(2)

(b)Calculate an estimate for the skew of the birth weights of the piglets.

...........................................................

(4)

(c)Interpret your answer to part (b).

.............................................................................................................................................

(1)

(d)Using only the information given in this question, explain whether it is possible to deduce that any of

the birth weights are outliers.

Justify your answer.

.............................................................................................................................................

(3)



(Total for question = 10 marks)



Q8.



Owen collected data about the number of people per km2 living in each of the 56 counties of England and

Wales in 2015

Some information about Owen's data is shown in this incomplete table.

(a)Work out the number of counties that have at least 600 people per km2.

...........................................................

(1)

(b)Use linear interpolation and the information in the table to find an estimate of the median number of

people per km2.

........................................................... people per km2

(3)

(c)(i)Using the information in the table, explain how the mean of Owen's data would compare with the

median of Owen's data.

.............................................................................................................................................

(ii)Explain whether the mean or the median is the most appropriate measure of central tendency to

use for Owen's data.

.............................................................................................................................................

(3)

Owen uses statistical software to draw a histogram to show the data he collected.

(d)Explain whether or not a histogram is appropriate.

.............................................................................................................................................

(1)

Owen prints his histogram but the page gets torn.

Here is what remains.

(e)Work out the value of r and the value of s in the table.

r = .............................. s = ..............................

(2)



(Total for question = 10 marks)



Q9.



In a town music competition, 6 groups competed against each other.

The table shows the marks awarded to each group by the invited independent judge.

The table also shows what the Mayor thought the rank order of the groups should be.

(Best group is given rank 1)

Using suitable calculations, investigate how much agreement there is between the judge

and the Mayor.

You may use the blank columns in the table for your working.

.............................................................................................................................................



(Total for question = 5 marks)



Q10.



The age and price of 12 used cars of the same type are plotted on the scatter diagram below.

One of the points on the scatter diagram represents an outlier.

(a)Draw a circle around the outlier.

(1)

(b)Comment on the price of the car represented by this point.

.............................................................................................................................................

(1)

Pearson's product moment correlation coefficient for the 12 cars, including the outlier, is calculated as –

0.662

With the outlier removed, Pearson's product moment correlation coefficient for the 11 cars is calculated as

–0.842

(c)(i)Give a reason why it might be appropriate to remove the outlier.

.............................................................................................................................................

(ii)Give a reason why it might not be appropriate to remove the outlier.

.............................................................................................................................................

(2)

With the outlier removed, Spearman's rank correlation coefficient for the data in the scatter diagram is

calculated as rs

(d)Describe fully how the value of rs should compare with –0.842

Give a reason for your answer.

.............................................................................................................................................

(3)



(Total for question = 7 marks)



Q11.



This time series graph shows information about the quarterly sales of soft drinks in a shop.

A trend line has been drawn on the graph.

(a)Describe the trend in the quarterly sales of soft drinks in the shop from 2015 to 2017

.............................................................................................................................................

(1)

(b)(i)Give an example of seasonal variation shown by the graph.

.............................................................................................................................................

(1)

(ii)Suggest a reason for this seasonal variation.

.............................................................................................................................................

(1)

The trend line was drawn using 4-point moving averages.

(c)(i)Using the data values for 2017 from the time series graph, calculate the final 4-point moving

average.

...........................................................

(2)

(ii)Plot your calculated 4-point moving average on the graph.

(1)



(Total for question = 6 marks)



Q12.



The table gives the price index number for the average rail fare in Great Britain for each

of six years, with 2012 as base year.

The table also gives some of the chain base index numbers for the same information.

(a)Find, correct to 2 decimal places, the chain base index number for 2017

...........................................................

(2)

Chris wanted to know the percentage increase in the cost of the average rail fare in

Great Britain between 2016 and 2017

Here is his working.

(b)Explain whether or not Chris is correct.

.............................................................................................................................................

(2)

The geometric mean of the chain base index numbers for 2013 to 2017 is 102.18

(c)Interpret this geometric mean in the context of the average rail fare in Great Britain.

.............................................................................................................................................

(2)



(Total for question = 6 marks)



Q13.



The table gives information about the change in the cost of a second class stamp from 2011 to 2017

By working out the geometric mean of 3 appropriate chain base index numbers, what can be deduced

about the average two-yearly change in the cost of a second class stamp from 2011 to 2017?

.............................................................................................................................................



(Total for question = 6 marks)



Q14.



The table shows the average cost of comprehensive motor insurance bought online each January from

2010 to 2013

(a)Using 2010 as the base year, find the price index (price relative) for motor insurance in January 2011

...........................................................

(2)

*(b)(i)Calculate the value of the chain base index number for motor insurance in January 2013

...........................................................

(ii)Interpret your answer.

.............................................................................................................................................

(4)



(Total for question = 6 marks)



Q15.



Tina has collected data on the deadlifts, in kilograms, for some female powerlifters.

She has summarised her results in the table.

Tina wants to calculate the mean deadlift for all 70 women.

She thinks that she has three possible methods.

Method AFind the mean of 134, 146 and 125

Method BWork out the total of (class midpoint of age × mean deadlift) for each class and divide by 70

Method CWork out the total of (mean deadlift × frequency) for each class and divide by 70

Determine which of these calculations Tina should use.

Explain why the calculation is appropriate.

.............................................................................................................................................



(Total for question = 2 marks)



Q16.



Nina suggests that each of the following problems can be answered by using a binomial distribution B(n,

p).

(a)Assess the suitability of using a binomial distribution model to answer each of the problems.

If a binomial model is suitable, you should consider any assumptions that must be made and give

possible values of n and p for the model.

If a binomial model is not suitable, you should explain why.

Problem 1

.............................................................................................................................................

Problem 2

.............................................................................................................................................

(6)

The probability that a particular machine has a fault is 7%.

A random sample of 6 of these machines are taken and each machine is checked.

(b)Work out the probability that at least 2 of these machines have the fault.

Give your answer correct to 3 decimal places.

...........................................................

(3)



(Total for question = 9 marks)



Q17.



X and Y are two events.

The Venn diagram shows information about the probabilities of events related to X and Y happening.

(a) Find

(i) the probability of event Y happening.

...........................................................

(ii)P(X and Y ),

...........................................................

(iii)P(Y | X).

...........................................................

(4)

Two different events A and B are independent.

P(A) = 0.8 and P(B) = 0.5

(b) Find P(A and B).

...........................................................

(2)



(Total for question = 6 marks)



Q18.



Fruitees sweets come in different flavours.

There are 8 sweets in a pack of mixed flavours and the flavours for each pack are chosen

at random.

The mean number of strawberry flavour Fruitees in a pack of 8 sweets is 2

Ed suggests that the number of strawberry flavour Fruitees in a pack of 8 sweets can be

modelled by a binomial distribution.

(a)By considering the conditions that make a binomial distribution a suitable model,

explain why Ed's suggestion is appropriate.

.............................................................................................................................................

(2)

One sweet is selected at random from a pack of Fruitees.

(b)Find the probability that the flavour of this sweet is strawberry.

...........................................................

(1)

Ed buys a pack of Fruitees.

(c)Find the probability that there will be exactly 3 strawberry flavour Fruitees in the pack.

...........................................................

(2)



(Total for question = 5 marks)



Question

Answer

Additional

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Mark

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B1

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

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Question

Answer

‘Additional

guidance

Mark

number

(@)

BI

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bedrooms

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Q4.



Question]

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

Q5.



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BI

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older

drivers’

0.

is

BO)

2°

BI

fora

correct

statement

comparing

gender.

(Condone

“male

drivers

make

more

claims

o.e.

and

reference

to

single

age-

groups,

but

‘there

are

more

male

drivers’

o.e.

is

BO)

If

both

age

and

gender

are

included

in

a

single

comment.

award

this

comment

for

the

feature

that

is

different.

‘NB:

If

BO

scored,

then a

single

incomplete

comment

eg.

“young

males

make

more

claims’

can

score

B1BO

(as

we

don’t

know

if

they

are

comparing age

or

gender).



Q6.



Question

Answer,

Additional

guidance

Mark

@)

Bl

72,74,

76,78,

8.0,

8.2

Mi

for

Sf

=

7.2

1+7.4%2+7.6x5+

(218.8

+

28)

Al

78

BI

for

midpoints

correct.

Condone

one

error.

(Can be

implied

by

218.8

seen)

M1

for

sensible

attempt

at

Ef

(x

must

be

a

consistent

value

within

each

class)

Al

for

awrt

7.8

not

from

wrong

method

@

)

nay

Bl

Correct

heights

Correct

horizontal

and

joined

All

correct

including

polygon,

scale

and

label

Different

vertical

scales

are

possible.

£

square

tolerance

on

plots.

BI

for

at

least

5

points

at

comect

height,

consistently

within

intervals.

(If

no

correct

scale

check

relative

heights:

,

2k,

5k,

9k, 8k,

38)

BI

for

at

least

5

correct

horizontal

plots

and

attempt

at

joining

(ignore

extra

lines)

BI

for

fully

correct

frequency

polygon

with

consistent

numbered

and

labelled

scale

(For

3"

B1

ignore

lines

joining

first/last

points

to

axis

but

not

to

each

other)

©

BI

ft

Negative

(kew)

BI

for

correct

conclusion

about

the

skewness

BO

for

negative

correlation

or

negative

trend

@



Q7.



‘Question

‘Additional

guidance

Mark

M1

fora

comrect

expression

for (2)

(@)

MI

the

standard

deviation

(allow

ore

without

square

root)

Al

0.7(0242...)

which

is

0.7

to

1

decimal

place

‘Tr

eet

0.7

hova

comrect

working

a)

Mi

for

using

linear

interpolation

|)

|

MiMedian=

2+—x05

total

de

cedian

Al

awrt

2.26

Al

226047...)

Allow

2.28

from

using

(n

+

1)/2

M1

for

using

30.29

3(mean

-

median)

MI'Skew

oT

standard

deviation

AL

answer

in

the

range

0.10

to

0.13

‘Al

for

answer

in

the

range

0.10

100.13

Allow

answer

in the

range

0.04

to

0.05 coming

from

use

of

(7

+

2

BI

fi

Glight

positive

skew)

so

the

weights

above

BI

fi

for

a correct

contextualised

(1)

(©

the

median

have

a

greater

spread

than

the

weights

interpretation

of

the

skew

below

the

median/more

piglets

have

a

weight

less

Allow

neatly

symmetric

than

the

mean

BI

Outlier

limits

are

[mean

=3sd]02and44

BI

for

using

mean

+3

sdto

@

obtain

awrt

0.2

and

awrt

4.4

B1

[0.2

<0.5]

So

there are

no

lower

outliers

BI

[4.0

<4.4<6.0]

We

don't

know

the

exact

weight

of

the

piglet

in

the

4.0

<w

<6.0

class,

so

cannot

determine

if

itis

an

outlier

BI

for

no

lower

outliers

BI

for

not

possible

to

determine

if

there

is

an

upper

outlier



Q8.



Question

Answer

Additional

guidance

Mark

@

BI

13

BI

for

correct

evaluation of

remaining

counties

@

)

MI

2004

(28-15)

Al

x

200

Al

=386

awst

Mi

for

identifying

Ind

class

and

attempting

to

find

median

value

within

the

class

Al

for

use

of

correct

fraction

and

class

width

(condone

use

of

28.5

for

28)

Al

for

value

rounding

to

386

(or

awrt

393

if

28.5

used)

oOo

©a)

BI mean

greater

(than

median)

BI

median

more

appropriate

with

attempt

to

give

a

reason

BI

...due

to (positive)

skew

BI

for

equivalent

statement

recognising

mean

will

be

greater

than

median

BI

for

correct

choice

AND

attempt

to

justify

BI

for

stating

data

is

skewed

This

may

be

seen

in

either

@

or

Gi)

@

BI

Appropriate

as

data

is

grouped

/

continuous

BI

for

conclusion

recognising

appropriateness

with

equivalent

reason

@

©

‘M1

0.0125

x

400

Alr=5

s=8

MI

for

attempting

area

of

bar

Alcao



Q9.



(Question

Answer

‘Additional

guidance

Mark

number

M1

Judge's

ranks:

2,1,3,5,6,4

1°

M1

for

correct

ranks

(accept

reversed)

2

2=4

M1

for

attempting

sum

of

squared

M1

d?=0+0+4+140+1

©6)

£9)

silos

anaes

wilh

at

honed

4

eacit

ae

3"

M1

for

complete

attempt

at

formula,

MYA

Se

including

“1

—

*

(allow

their

“6°)

ese

Al

for

0.83 or

better

‘AY

psiNS

earTCERTEA)

SS

al

&

ie

correct

interpretation

of

their

s

ancora

between

jade

Dependent

on

complete

attempt

to

use

and

Mayor.

formula

and

r

value

in

range —Ito

+1

Question

Answer

‘Additional

guidance

Mark

number

@)

BI

Point

circled

at

(15,

11000)

‘No

other

points

circled

@

®

BIA

The

value

of

this

car

is

significantly

higher

BI

comectinterpretationia

()

than

other

cars

(around

the

same

age)

context

Oo

BI

eg.

‘maybe

an

error

in

the

data’,

‘doesn't

fit

B1

fora

suitable

appropriate_|

@)

the

trend’

reason

for

not

including

the

ww

outlier

BI

eg.

‘includes

all

data’,

“genuine

value

B1

for

suitable

appropriate

reason

for

including

the

outlier

@

B2

closer

to

—1

(smaller/lower)

@)

BI

will

still

be

negative)

BI

(since

as

age

increases,

value

of

car

decreases

but)

not

at

a constant

rate

linear

pattern



Q10.



Q11.



‘Question

Answer

‘Additional

guidance

Mark

(a)

Bi

egsales

increase

(as

time goes

on)

BI

for

a

description

of

trend.

Accept

@

rising/upward

trend

(Condone

‘positive’

but

‘positive

correlation

is

BO)

@@

|

Bi

egsales

are

higher

in

each

quarter

3,

Bi

for

comectly

identifying

a

seasonal

o

OR

variation

lower

in

each

quarter

1

(i)

BI

egitis

warmer/

it

is

summer

there

B1

for

a

sensible

corresponding

suggestion

@

ismore

demand

for

drinks,

OR

itis

why

sales

are

higher

in

quarter

3

OR

why

colder

itis

winter

/there

is

less

lower

in

quaster

1

demand

for

drinks

(©@

M1

(180

+

260

+

300

+

240)

+4

MI

for

selecting

the

last

4

values

from

the

Q)

graph

(at

least

2

correct)

and

division

by 4

al

(=)

=245

Al

cao

+

(i)

B1

ft

Their

“245°

plotted

midway

between

B1ft

for

correct

horizontal

positioning

of

@

Q2&Q3.2017

their

moving

average

paertae

Answer

Additional

guidance

Mark

@)

M1 +44

100

@

eur

M1

for

complete

equivalent

working

Al

101.18

bess

(o)

B2

Not

correct

with

B2

for

correct

assessment

of

statement,

with

2)

acceptable

reason.

correct

reasoning

(allow

FT

from

their

(a))

eg

(B1

Not

correct

(with

attempt

at

reason))

©

this

is

1.3%

of

the

2012

average

rail

fare

*

should

use

chain

base

index

number

(so

increase

is

“1.18%")

#

increase

is

“1.18%

Ke)

B2

(on

average)

2.18%

B2

for

complete

answer

with

figures

and

2)

increase

per

year

interpretation.

(Otherwise

B1

for

2.18%

seen)



Q12.



Q13.



‘Question

Answer

‘Additional

guidance

‘Mark

M1

56/54

=

100

‘M1

for

correct

calculation

of

chain

base

©

index

number

Al

103.7

Al

for

awrt

103.7

M1

for

VI389

=

108

*

103.7

M1

ft

for

correct

calculation

of

the

geometric

mean

of

3

chain

base

index

sumbers

‘Al

ft

115.9

Alft

for

awrt

115.9

B1

ft

for

(average)

rate

of

‘increase’

per

B1

ft

for

correct

contextual

interpretation

as

two

years

rate

of

increasing

per

two

years

BI

ft...

is

‘159°%

BI

ft

for

correct

contextual

interpretation

of

the

value

for

their

geometric

mean

Question

Scheme

Marks

(@)

618.59

559

Mi

501.75

=

123.286

(Accept

123

or

better,

truncated

or

rounded)

Al

Q)

(y@

595.66

100)

5132

“1

si

=

91.454

(Accept

91

or

better,

truncated

or

rounded)

Al

*Gi)

Cost of

motor

insurance

decreased

over

the

year by 8.5%

(or

9%)

o.€

B2,1.08

a

[6]

Notes

(a)

M1

Full

method

(including

100)

using

correct

months.

(Implied by awst

123)

Al

for

123 or

better,

truncated

or

rounded

(e.g.

123,

123.2,

123.3

etc)

BUT

123%

or

£123

scores

MIAO

(b)@

M1

Fraction

using

comect

figures.

Al

for

91

or

better,

truncated

or

rounded

(e.g.

91,

91.4,

91.5

etc)

BUT

912%

or

£91

scores

M1A0

unless

the

same

error

is

seen

in

(a)

Gi)

QW

NB

ft

their

answer

to

(i)

only

if

it

is

an

attempt

at

an

index

number

G£no

answer

to

part

(j)

then

score

BO)

B2ft

for

correct

interpretation

including

all

three

features:

decrease/fall.

reference

to

period

of

‘one’

year,

and

figures

%

OR

BIft

for

their

9%

or

decrease

seen

(must

follow

through

from

their

(i)



Q14.



Question]

Answer

‘Additional

guidance

Mark|

B2

for

Method

C

AND

reference

to

dividing

B2

for

a

complete

assessment

of

the

appropriate

(2)

the

total

of

the

deadlifts

by

the

total

mumber

choice

with

reason

of

people

OR

BI

for

Method

C

with

attempt

at

reason

BI

for

an

incomplete

assessment

of

the

appropriate

choice

‘Question

[Answer

‘Additional

guidance

Mark

(@)_|

Problem

1

B3

for

fully

comect

assessment of

(6)

B3

suitability

and

assumptions

with

all

*

binomial

appropriate

as

6

bullet

points

correct

©

fixed

number

of

trials

©

two

possible

outcomes

~

getting

yellow/not

(B2

for

partially

correct

answer.

4

getting

yellow

bullet

points

correct

©

trials

are

independent

B1

for

partially

comrect

answer,

2

©

n=3andp=O.10e

bullet

points

correct)

«assume

probability

of

yellow

is

constant

Problem

2

B3

*

binomial

may

not

appropriate

as

although

there

is

a fixed

number

of

trials

and

two

possible

outcomes

—

five-set

/not

five-set

©

trials

are

not

independent,

the

people he

is

playing

change

(people

in

early

matches

are

likely

to

be

easier

to

beat

in

3

sets

than people

in

later

matches)

©

probability

is

unlikely

to

remain

constant

his

form

will

not

be

constant

OR

SC

B2

©

binomial

may

be

appropriate

as

2

fixed

number

of

trials

2

two

possible

outcomes

~

five-set

match/not

five-set

match

©

n=8andp

Soe

a

B3

for

fully

comrect

assessment of

suitability

and

assumptions

with

all

bullet

points

correct

(B2

for

partially

comect

answer,

2

bullet

points

correct

BI

for

partially

comrect

answer,

1

bullet

point

correct)

B2

for

complete

assessment

of

suitability

and

assumptions

with

all

4

bullet

points

correct

(BI

for

partially

correct

answer,

1

bullet

point

correct)



Q15.



Q16.



(@)

MI

093% or

6x

0.93"

x

0.07

M1

for

one

correct

probability

@

ML

1-(0.93°+

6 x

0.935

x

0.07)

‘M1

for

a

complete

method

Al

0.061

Al

for

awrt

0.061

Question

Answer

‘Additional

guidance

Mark

number

@@

[BI

@3+045)

07

For

probability

answers

accept

@)

equivalent

fractions,

decimals

or

percentages

@@i)

BI

03

gi)

yg,

03

05

Al

=06

)

MI

08x05

@

Al

=04



Q17.



Q18.



[Question]

Answer

Additional

guidance

‘Mar

number

(a)

B2

Suggestion

is

appropriate

B2

for

at

least

two

correct

conditions

@

because

(any

two

from):

referred

to,

with

at

least

one

in

context.

i

eed

maine

0

weet

(Otherwise

B1

for

one

correct

condition

8

in

each

packet

mentioned,

need

not

be

in

context.)

©

Flavours

are

independent

random

packing

©

Probability

(of

a

strawberry

Fruitee

would

be)

constant

©

Strawberry

&

not

strawberry

are the

only

two

outcomes

7

(o)

BI

(mean=

nxp

=

8Xp=2.

sop=)

o

1

toe

2

©

M1

0.25?

x

0.755

x

®C,

M1

for

correct

combination

of

probabilities

2)

Alft

=

0.2076.

with

attempt

at

binomial

coefficient

(e.g

from

Pascal's

triangle)

For

Alft

accept

0.21

or

0.208 with

correct

working.

ET

use

of

their

0.25

from

(b)

or

(a).



EDCO 735 LIBERTY UNIVERSITY Statistics paper 1 Questions review_2024.pdf

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