QUESTION 1

If the proportion of Mastercard transactions in a sample of various credit card transactions is equal to 0.664 and the sample size is 98, what is the margin of error for the corresponding 94% confidence interval to estimate the proportion of Mastercard transactions in the population? Assume that the conditions for the sampling distribution to be approximately normal are satisfied. Use Excel to calculate and round your answer to 4 decimals.

ANSWER: 0.0897

QUESTION 2

The population of computer parts has the size of 502. The proportion of defective parts in the population is 0.10. For the sample size of 228 taken form this population, find the standard deviation of the sampling distribution of the sample proportion (standard error). Round your answer to four decimal places.

ANSWER: 0.0199

QUESTION 3

Assume that the population of a store customers is infinite. For this population, the proportion of those customers who buy the service plan is 0.17. For the sample size of 208, find the standard deviation of the sampling distribution of the sample proportion (standard error). Round your answer to four decimal

ANSWER: 0.0261

QUESTION 4

To test the reliability of electric devices, a sample of 35 devices was taken. The mean number of minutes that the devices in the sample performed without errors was 184. The sample standard deviation was 12.1. What was the left boundary of 93% confidence interval to estimate the population mean? Use Excel for all computations and round your final answer to 2 decimals.

ANSWER: 182.07

JUST CHECKING IF MY ANSWERS ARE RIGHT