Question

The mean of 16 items was found to be 30.on rechecking it was found that two items were wrongly taken as 22 and 18 instead of 32 and 28 respectively. find correct mean. plzzz give

Answer 1

The correct mean is 31.25

Answer 2

Answer:

31.25

Step-by-step explanation:

We are given that  mean of 16 items was found to be 30

$Mean = \frac{\text{Sum of all items}}{\text{No. of items}}$

$30 = \frac{\text{Sum of all items}}{16}$

$30\times 16=\text{Sum of all items}$

$480=\text{Sum of all items}$

Now we are given that it was found that two items were wrongly taken as 22 and 18 instead of 32 and 28 respectively.

New Sum = 480-(22+18)+(32+28)= 480-40+60 = 500

Now new mean = $\frac{500}{16}$

                          = $31.25$

Thus the Correct  mean is 31.25