Psychology / 2 full pages @ least/ Research-Supported / No plagiarism / APA style

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Q1) Twenty six smokers were surveyed to ascertain the number of cigarettes each smoked for a 1 week period.

The results are as follows: 44 39 37 21 31 28 44 29 30 52 40 20 24 32 22 27 50 43 26 37 26 51 34 27 33 25

Create a frequency distribution with 5 classes using the headings: Class Limits, Class Boundaries, Frequency (f),

Midpoint (Xm), Cumulative Frequency (cf) Show details of your calculation for the class width.

Q2) Using the table created in Question 1 above, construct the following: (a) histogram (b) frequency polygon,

and (c) an ogive.

Please ensure that your graphs are neat and tide using a straight edge. Label your graph and show your scales

clearly.

Q3) Thirty Automobiles were tested for fuel efficiency in miles per gallon (mpg).

The results are shown below. Complete the following table and find the mean and modal class for the grouped

data

Class Boundaries Frequency (f) Midpoint (Xm) f.Xm f.Xm 2

7.5 - 12.5 3

12.5 - 17.5 5

17.5 - 22.5 15

22.5 - 27.5 5

27.5 - 32.5 2

Q5) Use the completed table in Question 3 above and find the variance and standard deviation for the grouped

data.

Q4) Use Chebyshev’s theorem for parts (a) and (b) below: (a) The average number of calories in a regular-size

bagel is 240 with a standard deviation of 30. Find the range in which at least 80% of the data would lie. (b) The

mean sale price for single family homes in the Baltimore area is $280,000. With a standard deviation of $20,000.

Find the minimum percentage of single family homes that would cost between $242,000. and $318,000.

Q6) Find the weighted mean price of four models of automobiles sold. The number and price for each model are

shown on the table.

Q7) The test scores for twelve students who took a statistic test are as follows: 82 , 96, 74 , 85 , 92 , 72 , 80 , 90 ,

88 , 79 , 98 , 78 (a) Find the percentile associated with the data value 80. (b) What data value corresponds to the

80th percentile?

Q8) Using your calculator, find the mean and standard deviation for the data values in question 7 (Q7). Using

these two values (mean and standard deviation), find the z scores for the data values 72 and 96. Give an

interpretation for these two z scores. Model Number Price A 6 $32,000 B 10 $25,000 C 12 $22,000 D 15 $18,000