SOLUTION: What Number increased by 12% and then decreased by 12% = 86.7328 I can't set up the equation properly, Thanks in advance for your help.

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Question 575970: What Number increased by 12% and then decreased by 12% = 86.7328
I can't set up the equation properly, Thanks in advance for your help.

Found 2 solutions by josmiceli, ankor@dixie-net.com:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +n+ = the number
the number increased by 12% is:
+n+%2B+.12n+
Now this number decreased by 12% is:
+n+%2B+.12n+-+.12%2A%28+n+%2B+.12n+%29+
given:
+n+%2B+.12n+-+.12%2A%28+n+%2B+.12n+%29+=+86.7328+
+n+%2B+.12n+-+.12n+-+.0144n+=+86.7328+
+n+-+.0144n+=+86.7328+
+.9856n+=+86.7328+
+n+=+86.7328%2F.9856+
+n+=+88+
check:
+n+%2B+.12n+-+.12%2A%28+n+%2B+.12n+%29+
+88+%2B+.12%2A88+-+.12%2A%28+88+%2B+.12%2A88+%29+
+88+%2B+10.56+-+.12%2A%28+88+%2B+10.56+%29+
+98.56+-+.12%2A98.56+
+98.56+-+11.8272+
+86.7328+
OK

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
What Number increased by 12% and then decreased by 12% = 86.7328
:
an increase of 12%, the multiplier is 1.12
a decrease of 12%, the multiplier is .88
:
.88(1.12x) = 86.7328
.9856x = 86.7328
x = 86.7328%2F.9856
x = 88