Question

Normal Distribution. The lifetime of a certain type of automobile tire (in thousands of miles) is normally distributed with mu = 42 and sigma = 5. What is the probability that a randomly chosen tire has a lifetime greater than 45 thousand miles? For this problem we want just the answer. Please give up to 4 significant decimal places, and use the proper rules of rounding.

Answer 1

Answer

using normalcdf

setting the following values

lower = 45

upper = 9999

mean = 42

sigma = 5

we get

P(X>45) = normalcdf(45,9999,42,5)

= 0.2743