The output voltage of a power supply is normally distributed

The output voltage of a power supply is normally distributed with a mean of 5 volts and a standard deviation of 0.02 volts. If the lower and upper specifications for voltage are 4.95 volts and 5.05 volts respectively, what is the probability that a power supply selected at random will conform to the specifications on voltage?

Solution

mu = 5

sigma =0.02

P(4.95<x<5.05)

= P(-2.5<x<2.5)

= 0.9876