SOLUTION: Please tell me what I am doing wrong. An employee's new salary is $28,140 after getting a 5% raise. What was the salary before the increase in pay? I just subtracted the 5% a

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Please tell me what I am doing wrong. An employee's new salary is $28,140 after getting a 5% raise. What was the salary before the increase in pay? I just subtracted the 5% a      Log On


   

Question 134731: Please tell me what I am doing wrong.
An employee's new salary is $28,140 after getting a 5% raise. What was the salary before the increase in pay?
I just subtracted the 5% and came up with $26,733 as my answer. It was wrong.
Thank you for your time
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
That is a common mistake.
5% of 28,140 will be a larger number than 5% of a number smaller than 28,140.
Let S be the old salary.
You are given that S + S*5% = 28140
S%281+%2B+0.05%29+=+28140+
S+%281.05%29+=+28140+
+S+=+28140%2F1.05
S+=+26800+
So 5% of 26800 = 1340
And 5% of 28140 = 1407
Do you see how you made your error?