SOLUTION: Denise did 7/8 of the problems on the quiz correctly and 5 incorrectly. She did all the problems. How many problems were there? I get 7/8 is 87.5%, but I can't figure up how t

Algebra ->  Percentages: Solvers, Trainers, Word Problems and pie charts -> SOLUTION: Denise did 7/8 of the problems on the quiz correctly and 5 incorrectly. She did all the problems. How many problems were there? I get 7/8 is 87.5%, but I can't figure up how t      Log On


   

Question 17087: Denise did 7/8 of the problems on the quiz correctly and 5 incorrectly. She did all the problems. How many problems were there?
I get 7/8 is 87.5%, but I can't figure up how to set up the problem.
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
You can let x = the number of problems on the quiz. Denise did (7/8) of x correctly and 5 of the problems incorrectly, so altogether she did (7/8)x + 5 problems. You can set up an equation as follows:
%287%2F8%29x+%2B+5+=+x Simplify and solve for x. Subtract (7/8)x from both sides.
5+=+x+-+%287%2F8%29x
5+=+%281%2F8%29x Multiply both sides by 8.
x+=+40
There were 40 problems on the quiz.