Chapter 2, Problem T2.2SPT

To determine

To find: the standard deviation is closest to for the normal distribution shown.

Answer to Problem T2.2SPT

3

Explanation of Solution

Given:

  

The mean of the normal distribution is at the peak of the normal distribution which is observed is at about 2

  $\mu \text{=2}$

The standard deviation of the normal distribution is then the distance from the vertical line at $\mu \text{=2}$ to the inflection point where the curve appears to be approximately a straight line. In this case, it is observed that this distance is about 3 and therefore the standard deviation is approximately 3

  $\sigma \text{=3}$

Graph:

  

Hence, the correct option is (d)