Question

Q1-Suppose a wholesaler of paints wants to estimate the actual amount of paint contained in 10 kg cans purchased from a paint manufacturing company. It is known from the manufacturer's specifications that the standard deviation of the amount of paint is equal to 0.05 kg. A random
sample of 49 cans is selected yields an average amount of paint per 10 kg can is 0.995 kg. What will be the margin of error when constructing a 97% confidence interval for the true population average amount of paint included in a 10 kg can?

Q2-A local magazine reports the typical shopper spends 8 minutes in line waiting to check out. A sample of 25 shoppers at Carrefour showed a mean of 7.5 minutes with a standard deviation of 2.5 minutes. Use a 0.05 level of significance to test whether the waiting time at Carrefour is less than that reported in the local magazine or not? Assume that the waiting times are normally distributed.

Write down the hypothesis, calculate the test statistic, the P-value and make a conclusion.

Answer 1