MATHS

Statcomprehensivefinal11.xlsx

Sheet1

Question 1
A sample of students was taken measuring the hours studied for a test and the score on the test (out of a possible total of 350 points)
x(#hours study)	y(test score)	Give the equation of the regression line
5	155	Predict test score for 12 hours of study
7	210	What is r
8	150	What % of the variation in test scores is explaines by #hours of study
10	192
11	245
13	260
15	270
18	275
20	290

Question 2

A cat breeder wants to estimate the true average weight of all Maine Coon cats.

A sample of 35 Maine Coons was taken and the sample mean was recorded at 14.7 lbs with standard deviation of 3.4 lbs.

Construct a 98% CI for mu the true average weight of the cats.

Give E the error of estimate

Give the upper and lower bounds to the CI

State in words what we can assert with 98% confidence

Question 3
Test the claim that the mean weight of chihuahuas is at least 10 lbs.
A sample of 60 chihuahuas found the mean of the sample to be 9.4 lbs. and standard deviation = 2.1 lbs.
Give the following:
µ					Draw the curve showing mu, x bar, z, shaded p value
x bar
s
n
standard error
z
p value
Should we reject the hypothesis

Question 4
To test the claim that it takes at least 16 minutes to perform a certain task, 6 test runs were taken.
The results were: 12, 13, 17, 13, 15, 14
Give the following
µ					Draw the curve showing mu, x bar, t, shaded p value
x bar
s
n
standard error
t
p value
Should the HYP be rejected?

Question 5
Test the null hypothesis: No significant difference in the average daily production of sewing machine operators
Operator1	Operator2	Operator3
10	11	10	Give the sample means and the grand mean
13	13	15	Show all numbers for SSA and SSW
9	8	13	Give the ANOVA table
11	16	11	What is the critical F for alpha = .05?
12	12	16	What is the p value?
			Should we reject the HYP?
			Is the difference in output for the 3 operators significant? (Answer yes or no)
			Draw the curve showing The Calculated F, the Critical F and the shaded 5% reject region
			Draw the curve showing the Calculated F and the shaded p value

Question 6
Test if stress level is independent of commuting time
		Stress level
	High	Moderate	Low
Commuting Time				Give the expected frequencies rounded to nearest tenth
Under 15 minutes	15	19	12	Give the calculated chi square
15-45 minutes	13	10	21	Give the critical chi square
Over 45 minutes	19	12	7	Give the p value
				Is stress level independent of commuting time? Yes or no.
				Draw the curve showing the calculated and critical F with the shaded reject region
				Draw the curve showing the calculated F and the shaded p value