Question

Rachel has taken 6 tests so far and has received scores of 83%, 92%, 79%, 88%, 89%, and 95%. What must Rachel receive on her seven test to have an average score of 90%?

Answer 1

Let the score on her seventh test be "x".

SO,

$\frac{83+92+79+88+89+95+x}{7} =90\\\\ \frac{526+x}{7}=90\\\\ 526+x=630\\\\x=630-526\\\\ \boxed{x=104}$

∴ He must get 104% on his seventh test to get an average score of 90%

Answer 2

104% in his next test