Question

Four friends are told that the average (mean) of their grades for their favorite class is 83.75%.

Kevin got 94%, Elizabeth got 78%, and Katherine got 83%.

Tyler's grade was not revealed. What's Tylers grade?

Answer 1

Tyler got 80%.

Explanation:

Represent Tyler's average by t.

Then .94 + .78 + .83 + t

-------------------------- = 83.75%

4

Multiplying both sides by 4, we get 2.55 + t = 3.35

so that t = 3.35 - 2.55 = 0.80

Tyler got 80%.