Question

In the following data one of the value of y is missing. Arithmetic means of x and y series are 6 and 8 respectively. `(sqrt(2) = 1.4142)`

x	6	2	10	4	8
y	9	11	?	8	7

Estimate missing observation

Answer 1

Let the missing observation be 'a'

x	6	2	10	4	8
y	9	11	a	8	7

`bar"x" = 6`,  `bar"y"` = 8, n = 5

`bar"y" = (sum_"y")/"n" = (35 + "a")/5`

∴ 8 = `(35 + "a")/5`

∴ a + 35 = 40
∴ a = 40 − 35
∴ a = 5
∴ Missing frequency = 5