SOLUTION: gerald has an average of 87 after 6 tests. What does Gerald need to get on the next test to finish with an average of 80 on all 7 tests?

Algebra ->  Average -> SOLUTION: gerald has an average of 87 after 6 tests. What does Gerald need to get on the next test to finish with an average of 80 on all 7 tests?      Log On


   



Question 963884: gerald has an average of 87 after 6 tests. What does Gerald need to get on the next test to finish with an average of 80 on all 7 tests?
Answer by LinnW(1048) About Me  (Show Source):
You can put this solution on YOUR website!
(6 * 87 plus the next test score )/7 = the new average score.
We want
%286%2A87+%2B+x+%29%2F7+%3E=+80
%28522+%2B+x+%29%2F7+%3E=+80
multiply each side by 7
%28522+%2B+x+%29+%3E=+80%2A7
%28522+%2B+x+%29+%3E=+560
add -522 to each side
+x++%3E=+560-522
+x++%3E=+38