Chapter 14, Problem 23SGA

To determine

To find the percentage of data in the interval $78-98$ .

Answer to Problem 23SGA

  $95.5\%$

Explanation of Solution

Given:

The mean of normally distributed data is $88$ and the standard deviation is $5$ .

Calculation:

The values within standard deviation and mean are obtained by adding the mean and deviation and subtracting them.

So these are-

  $88-5=83$ and $88+5=93$

  $t=\frac{93-83}{5}=\frac{10}{5}=2$

Now, using the page table on page no. 919 to obtain the percentage of data

  $t=2\to P=95.5\%$