Question

use the data 3, 4, 5, 7, 8, 9. without actually computing the standard deviation, determine the value below that best approximates the standard deviation.
choose the correct answer below.
a. 20
b. 7
c. 10
d. 2

Explanation:

Step1: Calculate the range

The range is \(R = 9 - 3=6\).

Step2: Use the range - rule - of - thumb

The range - rule - of - thumb states that \(s\approx\frac{R}{4}\). So \(s\approx\frac{6}{4} = 1.5\). Among the given options, \(2\) is the closest to \(1.5\).

Answer:

D. 2