The ages of students at a university are normally distributed with a mean of 21. What percentage of the student age is at least 21 years old?Question 10Select one:a.21%b.1.96%c.50%d.It could be any value, depending on the magnitude of the standard deviation

The professior of a university believes that the average age of the bachelor students  is 23. However, the tutor belives that the average age of the bachelor students differs from 23. To test the claim, they randomly selected 100 students, the average age was found to be 24.2 years. Assume the population standard deviation for the student age is 6 years. At the 1% level of significance, what is the test statistics?

A normal population has mean μ =33 and standard deviation σ =7.(a) What proportion of the population is between 18 and 29?

Suppose the scores on an exam are normally distributed with a mean μ = 75 points, and standard deviation σ = 8 points.The instructor wanted to "pass" anyone who scored above 69. What proportion of exams will have passing scores? 0.1587 0.75 0.2266 0.7734 −0.75

In an all boys school, the heights of the student body are normally distributed with a mean of 67 inches and a standard deviation of 5 inches. What percentage of the students are between 59 and 80 inches tall, to the nearest tenth?Statistics Calculator

The mean annual starting salary for Polytechnic graduates in 2019 was $36,280. Assume that the distribution of starting salaries follows the normal distribution with a standard deviation of $3,300. What percent of the graduates have starting salaries: a) Between $35,000 and $40,000? b) More than $45,000? c) Between $40,000 and $45,000?