The algebraic sum of deviations of 25 observations from 18 is 75, then the mean of observations is:

Correct option is D

Given:
Number of observations n = 25
Assumed mean A = 18
Algebraic sum of deviations = 75
Formula used:
​$$\bar{x} = A + \frac{\sum d}{n}$$​​
Solution:
​$$\bar{x} = 18 + \frac{75}{25}\\= 18 + 3\\= 21$$​​
The correct answer is (d) 21.