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# Basic Math/Unknown Percentage

Question
Hello:

Here is my question:

\$227.50 - (?% X \$227.50) = \$159.25

How would this be solved?  If I subtract \$227.50 from the right hand side of the equal sign, I get a negative number. If I subtract \$159.50 from \$227.50, there is nothing on the right hand side of the equal sign.

You're right, but you will also have a negative on the left hand side, so when you finish dividing, you'll have a positive number. If it makes more sense, subtract 159.50 from both sides, then add (?%x227.5) to both sides.

The way you want to do it:
\$227.50 - (?% X \$227.50) = \$159.25
\$227.50 - 227.5 - (?% X \$227.50) = \$159.25 - 227.5
-(?% X \$227.50) =  -68.25
-(?% X \$227.50)/-227.5 =  -68.25/-227.5
?% = .3, which is actually 3%

The way it might make more sense:
\$227.50 - (?% X \$227.50) + (?% X \$227.50) = \$159.25 + (?% X \$227.50)
227.5 = \$159.25 + (?% X \$227.50)
227.5 - 159.25 = 159.25 -159.25 + (?% x 227.5)
68.25 = (?% x 227.5)
.3 = ?%
Questioner's Rating
 Rating(1-10) Knowledgeability = 10 Clarity of Response = 10 Politeness = 10 Comment Thanks for the reply and explanation. I like the second method shown!

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#### Lynn Houston

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