Question

The random error in the arithmetic mean of 100 observations is x, then random error in the arithmetic mean of 400 observations would be
A. 4x
B. `(1)/(4)x`
C. 2x
D. `(1)/(2)x`

Answer 1

Correct Answer - B
Since error is measured for 400 observations instead of 100 observations. So error will reduce by `1//4` factor.