# John's annual salary after a raise of 15% is \$45,000. What was his salary before the raise?

hala718 | High School Teacher | (Level 1) Educator Emeritus

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Let us assume that John's salary before the raise was x

Then they gave him a 15% raise on his salary of x

Then, his current salary= original salary + The raise

45,000 = x + 0.15 x

45,000 = 1.15 x

==> x = 45,000/1.15 = 39,130  (approx.)

pohnpei397 | College Teacher | (Level 3) Distinguished Educator

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The answer to this is that John's previous salary was right about \$39,130.  Here is how you can find this answer:

Set up the equation like this:

45000/x = 115/100

This is because the relationship between 45000 and x (the original salary) is the same as the relationship between 115 and 100 (the new salary is 115% of the old).

Now you can cross multiply.  We will multiply 45000 by 100 and 115 by x.  That leaves us with

4,500,000 = 115x

divide both sides by 115 and you get

x = 39,130.43

itguy | eNotes Newbie

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Most teachers want you to show steps to answer. but if all you want is the answer, then this shortcut equation will suffice-> 45000/1.15 = 39130.43

krishna-agrawala | College Teacher | (Level 3) Valedictorian

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When an original amount or any other quantity is increased or raised by a given percentage the relationship between the original and the increased amount is given by the following formula.

x' = x*(100+p)/100   ...   (1)

Or

x = x'*100/(100+p)   ...   (2)

Where:

x = original amount

x' = increased amount

p = percentage increase

In the question it is given that:

Salary after raise = x' = \$45000

Percentage raise = p = 15

We have to find salary before raise, that is x.

Substituting values of x' and p in the formula (2) we get:

x = 45000*100/(100 + 15) = 4500000/115 = 39130.43

John's salary before raise was \$39130.43

lit24 | College Teacher | (Level 3) Valedictorian

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Let us assume that John's salary before the raise was y.

John's salary was increased by 15%

So John's salary after the increase will be: 15/100 x y = 15y/100

Therefore,     y + 15y/100 = 45,000

100y + 15y  = 45,000

115y = 4,500,000

y=   39,130.43

Answer: John's annual salary before the raise was \$ 39,130.43

neela | High School Teacher | (Level 3) Valedictorian

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If we assume Jhons sary at 100, after a ruse of 15% his salary is 100+15%0f 100 = 115.

So for a afetr rise of 15%, the present salary of %45000 and the 115 should  a same ratio to his  salary  before rise to \$100

So

salary before /100 = present salary/115 = 45000/115.

Salary before rise = (45000/115)100 = \$39,130.43

Or