Percent Decrease

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Percent Decrease

by nelnadi » Fri Jun 06, 2014 11:49 pm
Hi,

Can anyone help me answer the question below?

A certain juice manufacturer increased the number of ounces in Product N by 25 percent but did not change the price. What was the resulting percent decrease in the price per ounce of Product N?
(A) 10%
(B) 20%
(C) 25%
(D) 30%
(E) 35%

Best regards,
N.
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by GMATGuruNY » Sat Jun 07, 2014 1:31 am
nelnadi wrote: A certain juice manufacturer increased the number of ounces in Product N by 25 percent but did not change the price. What was the resulting percent decrease in the price per ounce of Product N?
(A) 10%
(B) 20%
(C) 25%
(D) 30%
(E) 35%
Before the increase:
Since 25% = 1/4, let the volume = 4 ounces.
After the increase:
Since the number of ounces increases by 1/4, the new volume = 4 + (1/4)4 = 5 ounces.

Let the price = the LCM of 4 and 5 = $20.
Before the increase:
Price per ounce = 20/4 = $5 per ounce
After the increase:
Price per ounce = 20/5 = $4 per ounce.

Percent decrease in the price = (difference between the prices)/(higher price) * 100 = 1/5 * 100 = 20%.

The correct answer is B.
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by kvcpk » Sat Jun 07, 2014 7:57 am
nelnadi wrote:Hi,

Can anyone help me answer the question below?

A certain juice manufacturer increased the number of ounces in Product N by 25 percent but did not change the price. What was the resulting percent decrease in the price per ounce of Product N?
(A) 10%
(B) 20%
(C) 25%
(D) 30%
(E) 35%

Best regards,
N.
its easier to assign 100 to the quantity and price since we are referring to percentages here.
So lets say 100 ounces = 100 dollars
after increase 125 ounces =100 dollars

Ideal price should have been 125 dollars.
hence decrease = (125-100)/125 * 100 = 20%

Hope this helps!!
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by theCodeToGMAT » Sat Jun 07, 2014 8:33 am
Number of ounces earlier = 100
Now = 125
Price = 100

Earlier = 100/100 = 1

Now = 100/125 = 4/5 = 0.20

Percentage = 20%
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