The mean age for all foothill college students for a recent fall term was 33.2. the population standard deviation has been pretty consistent at 15. suppose that twenty-five winter students were randomly selected. the mean age for the sample was 30.4. we are interested in the true mean age for winter foothill college students. let x = the age of a winter foothill college student.

construct a 95% confidence interval for the true mean age of winter foothill college students by working out then answering the exercise.

identify the following specifications. (round your answers to two decimal places.)
(a) lower limit

(b) upper limit

(c) error bound

a) Lower Limit = 24.52

b) Upper Limit = 36.28

c) Error bound = 5.88

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = 33.2

Sample mean, = 30.4

Sample size, n = 25

Alpha, α = 0.05

Population standard deviation, σ = 15

95% Confidence interval:

Putting the values, we get,

a) Lower Limit = 24.52

b) Upper Limit = 36.28

c) Error bound

from the figure we get,

the x axis shows   the months and,

the y-axis shows the number of satisfied customer.

each line or each cell in upward direction (y-axis) shows 500.

the appropriate scale for the y - axis is: -

a = 2000 customers

b = 4000 customers

c = 6000 customers

d = 8000 customers

e = 10000 customers

f = 12000 customers

g = 14000 customers