Hi vjesus12.

Let's see the question.

George made a mistake and he divided by 7 the sum of his test scores and he got 96, this implies that $$\frac{sum\ of\ test\ scores}{7}=96$$ $$\Rightarrow\ \ \ sum\ of\ test\ scores=672.$$ Now, since George had to divide by 8, we get $$Actual\ mean=\frac{sum\ of\ test\ scores}{8}=\frac{672}{8}=84.$$ This implies that the correct answer is the option B.

I hope this explanation may help you.

VJesus12 wrote:George tried to compute the mean average of his 8 test scores. He mistakenly divided the correct sum of all of his test scores by 7 and got an average of 96. What is George's actual mean test score?

(A) 80
(B) 84
(C) 96
(D) 100
(E) 108

The correct sum is 7 x 96 = 672, so the correct average is 672/8 = 84.

Answer: B