The mean of 200 items was 50. Later on, it was discovered that the two

1.	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.
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 \(=\frac{10.180}{200}\) = 50.9

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.

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 \(=\frac{10.180}{200}\)

= 50.9