Question

A psychopathologist records the number of criminal offenses among teenage drug users in a nationwide sample of 1,201 participants. To measure the variance of criminal offenses, he computes SS = 10,800 for t his sample. Compute the standard deviation.

Answer 1

Answer:

Standard deviation = 3

Explanation:

Given

$N = 1201$

$SS = 10800$

Required

Determine the standard deviation

First, we need to determine the variance;

$Variance = \frac{SS}{N - 1}$

This gives:

$Variance = \frac{10800}{1201 - 1}$

$Variance = \frac{10800}{1200}$

$Variance = 9$

Know that:

$Variance = SD^2$

Where SD represents standard deviation

This gives

$9 = SD^2$

Take square root

$SD = \sqrt 9$

$SD = 3$