Question

The average of 27 numbers is 18. The average of 4 numbers out of the 27 is
the average of the rest of the numbers?​

Answer 1

Since average = sum of elements/ total number of elements.

Here 2 elements are given (18, 27)

The average is also given (30)

The total number of elements is 3.

Let the third element be x

So directly putting them in above equation gives

30=18+27+x/3

90=18+27+x

90=45+x

x=45

Hence we get the value of third element which is 45.

Answer 2

Given,

Average of 27 numbers = 18

Average of 4 numbers out of the 27 numbers = 41

To Find,

The average of the rest of the numbers.

Solution,

Since the average of 27 numbers is 18, then the sum of the 27 numbers will be:

= 27×18 = 486

While the sum of 4 numbers will be:

= 41×4 = 164

The sum of the rest of the 23 numbers will be:

= 486-164 = 322

The average of the rest of the 23 numbers will be:

= 322/23 = 14

Thus, the average of the rest of the numbers will be 14.