Question

The average of the 11 numbers in a list is 72. The average of the first two numbers is 18. What is the average of the last nine numbers? BTW I'm NOT in high school I thought I was "too young" so I selected an older age

Answer 1

Answer: You are funny :)

Step-by-step explanation: Visualise Average as concept of “give & take”.

Average of first 8 number = 21

Average of last 4 number = 18

If average of all 12 numbers is 18, then we have 8 x 3 = 24 extra from first eight numbers.

This extra is distributed over all 12 numbers increasing their average by 24/12 = 2.

=> Final average = 18 + 2 = 20

No equations no fuss.

Note : This method is for Aptitude Test takers and not for school homework.

:-)