Question

The amount of snowfall falling in a certain mountain range is normally distributed with a mean of 84 inches and a standard deviation of 10 inches. What is the probability that the mean annual snowfall during 25 randomly picked years will exceed 86.8 inches?

Round your answer to four decimal places.

A.0.4192

B.0.0808

C.0.5808

D.0.0026

Answer 1

Solution :

Given that ,

mean = = 84

standard deviation = = 10

= / n = 10 / 25 = 2

P( > 86.8) = 1 - P( < 86.8)

= 1 - P[( - ) / < (86.8 - 84) / 2]

= 1 - P(z < 1.4)

= 1 - 0.9192

= 0.0808

Probability = 0.0808

option B. is correct