Question

If the mean of frequency distribution is 8.1 and Σf_ix_i = 132 + 5k, Σf_i = 20, then k =?

Options

• 3

• 4

• 5

• 6

Answer 1

6

Explanation:-

Given:

Σf_ix_i = 132 + 5k, Σf_i = 20 and mean = 8.1

Then,

Mean `=(sumf_ix_i)/(sumf_i)`

`8.1 = (132 +5k)/20`

162 = 132 + 5k

5k = 30

k = 6