SOLUTION: if soeone got on their first 3 test, 91%,87%, and 86% what average must they receive on the fourth and fifth test to average 90% for all test?

Algebra ->  Average -> SOLUTION: if soeone got on their first 3 test, 91%,87%, and 86% what average must they receive on the fourth and fifth test to average 90% for all test?      Log On


   



Question 423903: if soeone got on their first 3 test, 91%,87%, and 86% what average must they receive on the fourth and fifth test to average 90% for all test?
Answer by linht117(37) About Me  (Show Source):
You can put this solution on YOUR website!
ave=sum of all terms/ # of terms
90=91+87+86+2x/5
90*5=91+87+86+8x/5*5
450=264+2x
450-264=264-264+2x
186/2=2x/2
93=x
answer is 93% for the 4th and 5th test