SOLUTION: If increasing 20 by P percent yields the same result as decreasing 60 by P percent, then what is P percent of 70?

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Question 1089004: If increasing 20 by P percent yields the same result as decreasing 60 by P percent, then what is P percent of 70?
Found 2 solutions by ikleyn, MathLover1:
Answer by ikleyn(52873) About Me  (Show Source):
You can put this solution on YOUR website!
.
We need to find P from the equation

20*(1+P) = 60*(1-P),

20 + 20P = 60- 60P,

20P + 60P = 60 - 20,

80P = 40  =====>  P= 0.5, or 50%.


Next, 50% percents of 70 is 35.


Answer. P = 50%,  and  50% percents of  70  is  35.


Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

increasing 20 by P percent:20%2B20%2AP%
decreasing 60 by P percent:60-60%2AP%
yields the same result:
20%2B20%2AP%=60-60%2AP%
60P%2B20%2AP%=60-20
=>80%2AP%=40
=>P%2F100=40%2F80
=>P%2F100=0.5
=>P=50
So, P=50% of 70 is: 70%2A%2850%2F100%29=7%2A5=35