SOLUTION: a kind teacher gives you 20 cents for every question you get right, but you have to pay the teacher 10 cents for every question you get wrong. After 30 questions you made a profit

Question 1049346: a kind teacher gives you 20 cents for every question you get right, but you have to pay the teacher 10 cents for every question you get wrong. After 30 questions you made a profit of $ 1.80
a) Form an equation with X representing the number of equations you got right
B) solve your equation to find how many questions you got rightr

Answer by jorel555(1290) (Show Source): You can put this solution on YOUR website!
Let n be the number of questions you got right. Then 30-n equals the number of questions you got wrong. So:
20n-10(30-n)=180
30n-300=180
30n=480
n=16
30-n=14
You got 16 questions right and 14 questions wrong. ☺☺☺☺
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