The number of telephone calls received at an exchange in 245 successive on2-minute intervals is shown in the following frequency distribution :

Compute the mean deviation about the median.

Given, Numbers of observations are given.

To Find: Calculate the Mean Deviation

Formula Used: Mean Deviation =

Explanation.

Here we have to calculate the mean deviation from the median. So,

We know, Median in the even terms ,

Therefore, Median = 4

Let x_i =Number of calls

And, f_i = Frequency

N = 245

Mean Deviation =

Mean deviation for given data =

Hence, The mean deviation is 1.49