SOLUTION: A number is increased by 25% and the resulting number is then decreased by 20%. the final number is what percent of the original number? -I used 100 as my original number, and whe

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Question 78060: A number is increased by 25% and the resulting number is then decreased by 20%. the final number is what percent of the original number?
-I used 100 as my original number, and when i increased it by 25% i got 125. when i proceeded to decrease that by 20% i got 105. that would put the final number being over 100% of the original number, but my answer key says 100% is the answer.
Answer by bucky(2189) (Show Source):
You can put this solution on YOUR website!
You did the first part correctly. You started with 100 and increased it by adding 25% of 100
to it. 25% of 100 is 25 and so you got 100 + 25 for a total of 125.
.
Now the problem asks you to decrease the resulting number (125) by 20%. So you take 20%
of 125 (125 * 0.20) and the result of this multiplication is 25. Then you take 25 from
125 and you get the book answer of 100.
.
I suspect that you took 20% of 100 and got 20 ... and when you subtracted that from 125
you got your answer of 105. But that's not quite what the problem asked you to do. The
problem said to take 20% of the resulting number ... and from the first part of the problem
the resulting number was 125.
.
An easy mistake to make. Hope that this clarifies the answer for you.