Question

the average of 10 number is 5. if each is multiplied by 3, the average of the new set of number will be.

Answer 1

average of 10 numbers = 5

total = 5 x 10 = 50

now

A1 + A2 + ... + A10 = 50

New set of numbers

=A1 x3+ A2 x 3 + ... + A10 x 3

= 3( A1 + A2 + ... + A10 )

= 3( 50 )

= 150

new average of 10 numbers

= 150/10

= 15