Stats Tests Part 2

9 randomly sampled students were asked how many hours of TV they watched last week.  x̅  was 3.5 h and s was 4 h. For 95% confidence and 8 degrees of freedom, t*=2.3. The stem plot was somewhat skewed to the right, with no outliers. What is the 95% conf. int. for m?

• a)3.5 ± (2.3×4)
• b)3.5 ± (2.3×4 / 9)
• c)3.5 ± (2.3×4×9)
• d)3.5 ± (2.3×4 / 3)

Tags

CCSS.HSS.IC.B.4

A tire manufacturer claims that one particular type of tire will last at least 50,000 miles.  A group of angry customers does not believe this is so.  They take a sample of 14 tires to test if the mean mileage of the tires is really less than 50,000.  What set of hypotheses are they interested in testing?

• a) H0: m = 50,000 vs. Ha: m < 50,000
• b)H0: x̅ = 50,000 vs. Ha: x̅ < 50,000
• c)H0: m = 50,000 vs. Ha: m ≠ 50,000
• d)H0: m = 50,000 vs. Ha: m > 50,000

A tire manufacturer claims that one particular type of tire will last at least 50,000 miles.  A group of angry customers does not believe this is so.  They took a sample of 14 tires to test if the mean mileage of the tires is really less than 50,000.  If 0.0100 < P-value < 0.0200, what decision should be made if testing at the a = 0.05 level?

• a)Reject H0 and conclude that the tires were not performing as claimed.
• b)Reject H0 and conclude that the mean tire life really is 50,000 miles.
• c)Do not reject H0 and conclude that the tires were not performing as claimed.
• d)Do not reject H0 and conclude that the mean tire life really is 50,000 miles. 

Which of the following symbols represents the sample proportion?

• a)p
• b) p̂
• c) x̅
• d)P-value

Tags

CCSS.HSS.IC.B.3

We want to test whether proportions from two populations are different from each other. What are the appropriate null and alternative hypotheses?

• a)H0: p1 = p2, Ha : p1 ≠ p2

• a)H0: p1 ≠ p2, Ha : p1 = p2

• a)H0 : p1 = p2, Ha : p1 > p2

• a)H0 : p̂1 = p̂2, Ha : p̂1 ≠ p̂2

The Mean of a set of data is represented by which Greek letter?

• mu
• beta
• alpha

Does South Lake Tahoe have the same ethnic makeup as that of the (known) distribution of California?  Five Hundred South Lake Tahoe residents were asked about their ethnicity.

• one sample mean interval
• one sample proportion test
• chi square test
• linear regression test

Tags

CCSS.HSS.IC.B.4

You are given a normal approximation and are told the mean is 10 with standard deviation 2. What is the range for 95% of the data?

• 8-12
• 6-14
• 10-14
• 4-16

Tags

CCSS.HSS.ID.A.4

A study is done to see how chocolate affects weight in women. They given each woman 2 ounces of chocolate each day and monitor their weight each week for 6 months. What is the response variable?

• Weight
• Chocolate
• 6 months
• 2 ounces

Tags

CCSS.6.SP.A.3

Your alpha level for a hypothesis test is 5%. You calculate a p-value of 0.03. What is the conclusion?

• Reject Ho, No evidence of Ha.
• Fail to reject Ho, No evidence of Ha.
• Reject Ho, Evidence of Ha.
• Fail to Reject Ho, Evidence of Ha.