Question

Given that the arithmetic mean of 500 items is 1000. However, at the time of calculations two items 1800 and 900 were wrongly taken as 1000 and 100. Please find the correct value of Arithmetic mean.

Answer 1

The correct value of Arithmetic mean is:

$A = 1000 + (1800 - 1000)/500 + (900 - 100)/500 = 1003.2.$