Question

The mean of 20 observations is 63.If an observation 50 is replaced by 90. Find the new mean.​

Answer 1

Answer:

The new mean is 65.

Step-by-step explanation:

Given that:

The mean of 20 observations is 63.

An observation 50 is replaced by 90.

To Find:

The new mean.

We know that:

Mean = (Sum of observations)/(Number of observations)

We have:

Number of observations = 20

Mean = 63

⟶ 63 = (Sum of observations)/20

⟶ Sum of observations = 63 × 20

⟶ Sum of observations = 1260

Now finding the new mean:

We have.

Number of observations = 20

As an observation 50 is replaced by 90.

Sum of observations = 1260 - 50 + 90 = 1300

⇒ Mean = 1300/20

⇒ Mean = 65

Hence,

The new mean = 65

Answer 2

Thus the new mean is 54.5 .

Hope it helps :)