SOLUTION: Please help. I cannot find a sample formula to solve this problem. It is estimated that 5% of rebuilt alternators do not last through the 90−day warranty period. If a parts

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Please help. I cannot find a sample formula to solve this problem. It is estimated that 5% of rebuilt alternators do not last through the 90−day warranty period. If a parts      Log On


   

Question 86903This question is from textbook Beginning Algebra
: Please help. I cannot find a sample formula to solve this problem.
It is estimated that 5% of rebuilt alternators do not last through the 90−day warranty period. If a parts store had 6 bad alternators returned during the year, how many did they sell? This question is from textbook Beginning Algebra

Answer by tutorcecilia(2152) About Me  (Show Source):
You can put this solution on YOUR website!
Use this formula:
Part/Whole = %/100
Let (Whole) = w
6/w=5%/100 [plug-in the values and solve for the missing value (Whole)]
(6)(100)=(w)(5) [cross-multiply]
600=5w [solve for the Whole(w) variable]
600/5=w/5
120=w
.
So, the store sold 120 units. 6 out of 120 were defected:
6/120=5%/100
.05=.05