Question

the mean of 20 numbers is 18 if 3 is added to each of the first ten no find the mean of the new no

Answer 1

Answer:

19.5

Step-by-step explanation:

Mean : The value obtained after dividing the sum of quantities by the number of quantities is known as the mean. It is also known as an average.

Also, Mean = Sum of Quantities/ Number of Quantities.

Given, the mean of 20 numbers is 18.

Then, their sum will be 20 x 18.

Sum = 360

Now, if 3 is added to each of the first 10 numbers, then, the new sum will be

360 + ( 3 x 10 )

= 360 + 30

= 390

Then, the new mean will be 390/20 ( Since, Mean = Sum of Quantities/ Number of Quantities, )

Therefore, the new mean will be 19.5.

Hope it Helps!