SOLUTION: Sally was given 5 cents for each test she passed but had to return 10 cents for each she failed. At the end of 3 months she passed four times as many tests as she failed and she ha

Question 154974: Sally was given 5 cents for each test she passed but had to return 10 cents for each she failed. At the end of 3 months she passed four times as many tests as she failed and she had earned 20 cents. How many tests did she pass?
Hi: My teacher handed this out today and is reprinted from a textbook, but I do not have the IBN number as the textbook is at school.
Thanks.
Answer by checkley77(12844) (Show Source): You can put this solution on YOUR website!
5(4x)-10x=20
20x-10x=20
10x=20
x=20/10
x=2 failed tests.
4*2=8 passed tests.
Proof:
5*8-10*2=20
40-20=20
20=20

RELATED QUESTIONS
How would you write this as an algebraic equation? During a school year a student was... (answered by stanbon)

Liann bought several apples at the rate of 3 for 35 cents. She sold 9/10's of them at 25... (answered by ankor@dixie-net.com)

Liann bought several apples at the rate of 3 for 35 cents. She sold 9/10's of them at 25... (answered by oscargut)

Sandy held a garage sale during which she charged a dime for everything, but accepted a... (answered by solver91311)

Sandy held garage sale during w/c she charged a dime for everything but accepted a nickel (answered by josmiceli,Theo)

What is the formula for solving this: Sour balls are 2 cents each, and lollipops are 5... (answered by scott8148)

Pam bought several cartons of Giggle Fruit Drinks to sell during the track meet, she paid (answered by fractalier)

Pam bought several cartons of Giggle Fruit Drinks to sell during the track meet. She paid (answered by fractalier)

Pam bought several cartons of Giggle Fruit Drinks to sell during the track meet. She paid (answered by josmiceli)