Question

Mean of 30 observation is x. It was found out that 23 was misread as 32.If tha actual mean is y what is the value of x-y

Answer 1

Answer:

The mean of those observations are 30

So The sum of observations is 30×100=3000

The wrong observations are 32 and 12

Those are to be subtracted from sum of observations

So, 3000−32−12=2956

The correct observations are 23 and 11

Those are to be added

So, 2956+23+11=2990

The mean is given by

100

2990

=29.9

Example is written above