The mean of 200 items was 50. Later on, it was discovered that the two items were misread as 92 and 8 instead of 192 and 88. Find the correct mean.

Question

Philoid · Accepted Answer

The mean of 200 items = 50

Then the sum of 200 items = 200 * 50

= 10,000

Correct values = 192 and 88

Incorrect values = 92 and 8

Therefore, correct sum = 10,000 – 92 – 8 + 192 + 88

= 10,180

Therefore, correct mean =

= 50.9