Question

The forestry service personnel at a national forest are estimating the average height of the trees in the forest. They measure the heights of 31 trees and prepare the histogram above. What percentage of the trees are less than 75 feet tall?
A. 45.2
B. 80.6
C. 19.4
D. 77.4

Answer 1

Answer:

The correct answer is A. 45.2

Step-by-step explanation:

1. Let's review all the information provided for solving this question:

Number of trees of the sample = 31

Number of trees of the sample with a height between 60 and 65 feet tall height = 3

Number of trees of the sample with a height between 65 and 70 feet tall height = 3

Number of trees of the sample with a height between 70 and 75 feet tall height = 8

Number of trees of the sample with a height between 75 and 80 feet tall height = 10

Number of trees of the sample with a height between 80 and 85 feet tall height = 5

Number of trees of the sample with a height between 85 and 90 feet tall height = 2

2. Let's calculate the percentage of the trees that are less than 75 feet tall:

Percentage of the trees less than 75 feet tall = [(Number of trees of the sample with a height between 60 and 65 feet tall + Number of trees of the sample with a height between 65 and 70 feet tall + Number of trees of the sample with a height between 70 and 75 feet tall)/Number of the trees of the sample] * 100

Replacing with the real values, we have:

Percentage of the trees less than 75 feet tall = [(3 + 3 + 8)/31] * 100

Percentage of the trees less than 75 feet tall = [(14)/31] * 100

Percentage of the trees less than 75 feet tall = 0.451613 * 100

Percentage of the trees less than 75 feet tall = 45.1613% = 45.2% (Rounding to one decimal place)

The correct answer is A. 45.2