Ian's Tree Farm Grows Spruce Trees for Plant Nurseries

Multiple Choice

Ian's Tree Farm grows spruce trees for plant nurseries. The average annual increase in tree diameter is 7.9 centimetres with a standard deviation of 1.3 centimetres. A random sample of n = 50 trees is collected. What is the probability of the sample mean being less the 7.4 centimetres?

A) 0.0033
B) 0.4977
C) 0.5023
D) 0.9977
E) 0.9954