An admissions director wants to estimate the mean age of all students enrolled at a college. the estimate must be within 1.3 years of the population mean. assume the population of ages is normally distributed.(a) determine the minimum sample size required to construct a 90% confidence interval for the population mean. assume the population standard deviation is 1.5 years.

4

Step-by-step explanation:

For given Population standard deviation , the formula to sample size is given by :-

, where z* = Two-tailed critical value.

E = Margin of error.

Given : years

We know that , Critical value for 90% confidence interval : z* = 1.645

Margin of error : E=1.3 years

Then, the minimum sample size required to construct a 90% confidence interval  for the population mean will be :-

[Rounded to the nearest whole number.]

Hence, the minimum sample size required = 4

circle area = pi * radius^2

if diameter = 10 then radius = 5

circle area = pi * 5^2

circle area = pi * 25

circle area = 78.5398163397 square units

step-by-step explanation: