Question

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 1

Mean of 200 items=50

$\therefore Total=50\times 200=10000$

The number were misread as 92 and 8 instead of 192 and 88.

$\therefore Difference=192-92+88-8=180$

$\therefore Newtotal=10000+180=10180andnewmean=\frac{10180}{200}=50.9$