Question

The average of 25 observations is 28. Later it was found that an observation 90 was
wrongly entered as 40. What is the new average after correction?​

Answer 1

Answer I is 30

Mark the other person brainliest

Answer 2

Given:

The average of 25 observations is 28. Later it was found that an observation 90 was wrongly entered as 40.

To find:

The correct new average.

Solution:

The correct new average is 30.

To answer this question, we will follow the following steps:

As given, we have,

Average of 25 observations = 28

i.e.

$\frac{sum \: of \: 25 \: observations}{25} = 28$

So,

Sum of 25 observations

$= 28 \times 25 = 700$

Now,

As observation 90 was wrongly entered as 40.

This means,

The correct sum of 25 observations

$= 700 + (90 - 40)$

$= 700 + 50 = 750$

So,

The new average after correction

$= \frac{750}{25}$

$= 30$

Hence, the correct new average is 30.