The life expectancy of computer terminals is normally distributed with a mean of 4 years and a standard deviation of 1 year. What is the probability that a terminal will last 5 years or less?

The probability that a terminal will last 5 years or less is 0.8413

Step-by-step explanation:

Given:

μ = 4 years

σ = 1 year

Z = (x-μ) : σ

Z = (5-4) : 1 = 1

The standard normal distribution table provides the probability that a normally distributed random variable Z, with mean equal to 0 and variance equal to 1, is less than or equal to z.

For z = 1 ⇒ P (z≤1) = 0.8413