The mean of 20 number is 59. If 3 is added to each number what will be the new mean?

Question

Philoid · Accepted Answer

Given that, mean of 20 numbers = 59

Mean can be given by

Where, ∑x = Sum of all observations

& n = Total number of observations

Here, Mean = 59 and n = 20.

So,

⇒

⇒ ∑x = 59 × 20

⇒ ∑x = 1180

We have sum of all observations = 1180

If 3 is added to each of the 20 numbers, then new sum of all observations = 1180 + (20 × 3)

⇒ New sum of all observations = 1180 + 60 = 1240

Now, we have fresh data: ∑x’ = 1240, n = 20

⇒ New mean = 62

Thus, new mean of the observation is 62.