Question

The arithmetic mean (average) of four numbers is 85. If the largest of these numbers is 97, find the mean of the remaining three numbers. I cannot solve this. Please help on it.

Answer 1

81

Explanation:

Let's do this systematically:

Four numbers: a, b, c, d

Whose mean is 85:
`(a + b + c + d)/(4) = 85`

Whose largest number is 97:
`(a + b + c + 97)/(4) = 85`

Lets solve for the other numbers:

a+b+c+97 = 85*4 = 340

340 - 97 = 243

a+b+c = 243

at this point it doesn't matter what the numbers are, they just need to add up to 243.

We can do 243÷3=81, which is our answer