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Status:Impossible is not a fact. It's an opinion. It's a dare. Impossible is nothing.
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Re: If the price increased by x% from 2001 to 2002 and by y% fro [#permalink]
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This is a trap called "lone wolf". Wolves are loner. The question will imply that you will need two equations to solve since there are two variables. However we don't need two equations. Back to the question. If you consider the general formula for percentage change is
X+y+xy/100
S2 reduces to this form . Hence sufficient
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Re: If the price increased by x% from 2001 to 2002 and by y% fro [#permalink]
Assume price in 2001 = 100
--> price in 2002 = 100(1+x/100) =100 + x
--> price in 2003 = (100+x)(1+y/100) = 100 + x + y + xy/100

from 2) x + y + xy/100 =8 --> sufficient.
1) is not sufficient.

it would of course be faster if one remembered the formula.
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Re: If the price increased by x% from 2001 to 2002 and by y% fro [#permalink]
asmit123
If the price increased by X% from 2001 to 2002 and by Y% from 2002 to 2003,what is the % increase from 2001 to 2003?
1. XY = 30
2. 100X + 100Y + XY = 800
Price 2001 =P
=>Price in 2002, P + x% of P = P + Px/100 = P(1 + x/100)
=> Price in 2003, P(1 + x/100)(1 + y/100)

Percentage Increase =>(P ((1 + x/100)(1 + y/100) -1)/P) *100
=>(((1+X/100)(1+Y/100))-1 ) *100
=>(100+X)(100+Y)-100
=>100X+100Y+XY+10000-100
=>800+10000-100

Hence B
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Re: If the price increased by x% from 2001 to 2002 and by y% fro [#permalink]
%age increase = {P(1+x/100)(1+y/100) - P}/P

where P is the original price.

(10000 + 100y + 100x + xy)/100000 - 1

Clearly, the answer is B.
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Re: If the price increased by x% from 2001 to 2002 and by y% fro [#permalink]
rephrasing question we have x+y+(xy/100) and thats what we need to find.

1. Not sufficient . there are different possible x and y that satisfy the given condition.

2. Sufficient . as we have the expression in similar form.

Answer is B.
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Re: If the price increased by x% from 2001 to 2002 and by y% fro [#permalink]
amitanand
If the price increased by x% from 2001 to 2002 and by y% from 2002 to 2003, what is the percentage increase from 2001 to 2003?

(1) xy = 30
(2) 100x + 100y + xy = 800

Let price, P be 100.

after x% increase, price P1 = 100+x

After y% further increase, price P2 = 100+x + (100+x)*(y/100)

% increase = Increase in price / original price = (p2-p)*100/p = (100 X +100Y+xy)/100.

B gives numerator value. so sufficient but A is not.
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Re: If the price increased by x% from 2001 to 2002 and by y% fro [#permalink]
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Re: If the price increased by x% from 2001 to 2002 and by y% fro [#permalink]
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