Suppose that the time required to complete a 1040R tax form is normally distributed with a mean of 110 minutes and a standard deviation of 15 minutes. What proportion of 1040R tax forms will be completed in at least 136 minutes? Round your answer to at least four decimal places.

Write the formulae  60% of all the students passed an exam. If a random sample of 10 students is selected, What is the mean and the standard deviation ?

The IRS claims it takes an average of 3.7 hours to complete a 1040 tax form. Assume the time t the form is normally distributed with a standard deviation of 15 minutes or 0.25 hours. complete Use the Cumulative Z-Score Table to answer the following questions. Write your answer as a percent using 2 decimal places. What percent of people would you expect to complete the form in less than 3.45 hours? What percent of people would you expect to complete the form-in more than 3.45 hours? What percent of people would you expect to complete the form in less than 3.4 hours? What percent of people would you expect to complete the form in more than 3.4 hours? What percent of people would you expect to complete the form between 3.4 and 3.45 hours?

Students must have GPAs in the top 7.5% of the school to be accepted into the honour society. When the average GPA is 2.92 with the standard deviation of 0.29, what GPA do you have to have to be accepted? Show all your work. Round off to 100th.

A psychologist has designed a questionnaire to measure individuals' aggressiveness. Suppose that the scores on the questionnaire are normally distributed with a standard deviation of 80. Suppose also that exactly 15% of the scores exceed 750. Find the mean of the distribution of scores. Carry your intermediate computations to at least four decimal places. Round your answer to at least one decimal place.