The average life of a smartphone is 7 years with a standard deviation of 1 year. Assuming that the lives of these phones follow approximately a normal distribution, using a random sample of n = 9 find the probability that the mean life of such smartphones fall between 6.4 and 7.2 years. A. 69.47% B. 28.60% C. 42.42% D. 30.50%

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018
18th Edition
ISBN:9780079039897
Author:Carter
Publisher:Carter
Chapter10: Statistics
Section10.4: Distributions Of Data
Problem 19PFA
icon
Related questions
Question
100%

The average life of a smartphone is 7 years with a standard deviation of 1 year. Assuming that the lives of these phones follow approximately a normal distribution, using a random sample of n = 9 find the probability that the mean life of such smartphones fall between 6.4 and 7.2 years.

A. 69.47%

B. 28.60%

C. 42.42%

D. 30.50%

Expert Solution
steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897…
Glencoe Algebra 1, Student Edition, 9780079039897…
Algebra
ISBN:
9780079039897
Author:
Carter
Publisher:
McGraw Hill