Question

Suppose that the lifespan of laptops is normally distributed with a mean of 24.3 months and
standard deviation of 2.6 months. If USP provides its 33 staff with a laptop, find the probability
that the mean lifespan of these laptops will be less 23.8 months.

Answer 1

Answer:

probably it will be defined by the 24.3/2.6 that is 21.7

Answer 2

Answer:

13.57% is the probability that mean lifespan of the laptop that is less than 23.8.

Step-by-step explanation:

x= 23.8

n=33

μ= 24.3

σ=2.6

Z= (x-μ)/(σ/√n)

Z=(23.8-24.3)/(2.6/√33)

Z= -0.5/0.452

Z=-1.10

Now look for 1.10 in the Standard Normal Distribution Table you'll find 0.3643..

0.5-0.3643 (because it says lesser than)

=0.1357

Therefore, the probability that the mean lifespan of the laptop that is less than 23.8 is 13.57%.