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Percent question
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07 Jan 2015, 08:22
07 Jan 2015, 08:22
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Question Stats:
100% (00:17) correct
0% (00:00) wrong based on 1 sessions
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I came across a percent question that was phrased something like this:
A store reduced the sale price of an item by another 20%, which was a total of 60% off of the original price. What is the original price of the item?
How do you solve a question like this, if you are not given any "seed" number?
A store reduced the sale price of an item by another 20%, which was a total of 60% off of the original price. What is the original price of the item?
How do you solve a question like this, if you are not given any "seed" number?
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Joined: 16 May 2014
Posts: 592
Given Kudos: 0
GRE 1: Q165 V161
Re: Percent question
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10 Jan 2015, 07:06
10 Jan 2015, 07:06
Expert Reply
I think this question is still missing some data. I think they should have given more data about the final price after the two sets of discount.
Just a trick i will share if you don't know already...
When there are two successive percentage changes P1 & P2.. the ultimate overall percentage change is ...
\(P_final = P1 + P2 + (P1*P2/100)\)
So in this particular case \(P1 = -60 & P2 = -20\)
P_final = -60 - 20 + (-60)*(-20)/100
= -80 + 12
= -68 % (Overall decrease)
So if the initial price was $ 100 now it should be $ 32.
Hope this helps. But still the question you said is incomplete.
Just a trick i will share if you don't know already...
When there are two successive percentage changes P1 & P2.. the ultimate overall percentage change is ...
\(P_final = P1 + P2 + (P1*P2/100)\)
So in this particular case \(P1 = -60 & P2 = -20\)
P_final = -60 - 20 + (-60)*(-20)/100
= -80 + 12
= -68 % (Overall decrease)
So if the initial price was $ 100 now it should be $ 32.
Hope this helps. But still the question you said is incomplete.
Re: Percent question
[#permalink]
05 Jul 2015, 19:45
05 Jul 2015, 19:45
To solve such questions quickly you should consider 100 as the initial seed value.
