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pool

by okigbo » Mon Nov 09, 2009 11:17 am
If Pool Y currently contains more water than Pool X, and if Pool X is currently filled to 2/7 of its capacity, what percent of the water currently in Pool Y needs to be transferred to Pool X if Pool X and Pool Y are to have equal volumes of water?

(1) If all the water currently in Pool Y were transferred to Pool X, Pool X would be filled to 6/7 of its capacity.

(2) Pool X has a capacity of 14,000 gallons.
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by palvarez » Mon Nov 09, 2009 1:14 pm
C_y > C_x
C_x = (2/7) V_x

What is (1/2)(C_y - C_x)/C_y = 1/2 ( 1- (C_x/C_y))

1. C_y + C_x = (6/7) V_x
C_y = (4/7)V_x
C_x/C_y = 1/2

Sufficient.

A is the answer
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by viju9162 » Mon Nov 09, 2009 10:30 pm
Hi Palvarez,

I understand that 4/7th of water is transferred to pool X. However, I didn't quite understand how to determine percent of the water transferred from Y ..

Regards,
Viju
"Native of" is used for a individual while "Native to" is used for a large group
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by palvarez » Mon Nov 09, 2009 10:34 pm
You are given a and b, such that a > b

how to make them even?

Take the difference and split between two.

a - (a-b)/2 = b + (a-b)/2


In other words, you need to know how much percent of a is (a-b)/2? In order to answer that question, if you know a/b or b/a, that is enough.

C = current content
V = actual volume.
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