SOLUTION: You have a test score of 51. There were 20 problems on quiz. You received 5 points for each correct response and a 2 point deduction for each one incorrect. How many did you cor

Algebra ->  Expressions-with-variables -> SOLUTION: You have a test score of 51. There were 20 problems on quiz. You received 5 points for each correct response and a 2 point deduction for each one incorrect. How many did you cor      Log On


   



Question 969768: You have a test score of 51. There were 20 problems on quiz. You received 5 points for each correct response and a 2 point deduction for each one incorrect. How many did you correct.
Please tell me how to set up and solve equation.

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
You have a test score of 51.
There were 20 problems on quiz.
You received 5 points for each correct response and a 2 point deduction for each one incorrect. How many did you correct.
:
let x = no. of correct problem
then
(20-x) = no. of incorrect problems
:
5x - 2(20-x) = 51
5x - 40 + 2x = 51
5x + 2x = 51 + 40
7x = 91
x = 91/7
x = 13 correct problems
:
:
Check this, we know that he got 7 problems wrong
13 * 5 = 65
7 * -2 = -14
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results: 51