Question

To determine the average height of trees in a national forest, 10 trees are randomly selected. Their heights in feet are 85.4,87.6,87.1,85.6,85.9,85.3,84.9,83.7,84.0,and 85.2
. To ensure the accuracy of the data, another set of 10 trees is randomly selected. Their heights are 87.1,88.0,84.2,85.3,86.5,84.2,83.2,84.1,85.2,and 87.3
. What is the difference between the mean heights of the trees of these two random samples? Express your answer as a decimal. Do not round your answer.(1 point)
feet

Answer 1

First sample mean = (85.4+87.6+87.1+85.6+85.9+85.3+84.9+83.7+84.0+85.2)/10 = 854.7/10 = 85.47 ft
Second sample mean = (87.1+88.0+84.2+85.3+86.5+84.2+83.2+84.1+85.2+87.3)/10 = 855.1/10 = 85.51 ft

Difference = 85.51 − 85.47 = 0.04 feet (the second sample mean is 0.04 ft larger).