Question

7) (1 point) A package delivery service wants to compare the proportion of on-time deliveries for two of its major service areas. In City A, 251 out of a random sample of 310 deliveries were on time. A random sample of 324 deliveries in City B showed that 243 were on time.

1. Calculate the difference in the sample proportion for the delivery times in the two cities.

p^CityA−p^CityBp^CityA−p^CityB =

2. What are the correct hypotheses for conducting a hypothesis test to determine whether the proportion of deliveries that are on time in City A is different from than the proportion in City B?

A. H0:pA=pBH0:pA=pB, HA:pA<pBHA:pA<pB
B. H0:pA=pBH0:pA=pB, HA:pA≠pBHA:pA≠pB
C. H0:pA=pBH0:pA=pB, HA:pA>pBHA:pA>pB

3. Calculate the pooled estimate of the sample proportion.

p^p^ =

4. Is the success-failure condition met for this scenario?

A. No
B. Yes

5. Calculate the test statistic for this hypothesis test.

? z t X^2 F  =

6. Calculate the p-value for this hypothesis test.

p-value =

7. Based on the p-value, we have:
A. some evidence
B. very strong evidence
C. extremely strong evidence
D. strong evidence
E. little evidence
that the null model is not a good fit for our observed data.

8. Compute a 90% confidence interval for the difference p^CityA−p^CityBp^CityA−p^CityB.

( , )

Answer 1