A certain candy manufacturer reduced the weight of Candy Bar M by 20

Question

A certain candy manufacturer reduced the weight of Candy Bar M by 20 percent buy left the price unchanged. What was the resulting percent increase in the price per ounce of Candy Bar M?

(A) 5%
(B) 10%
(C) 15%
(D) 20%
(E) 25%

fluke · Accepted Answer

Before:
$1->1 oz
Price: 1/1 $/oz
After:
$1->0.8 oz
Price: 1/0.8 $/oz = 1.25 $/oz

Thus, the price increased per oz is 25cents.
25cents is 25% of $1

Ans: "E"

toughmat · Answer

I used Algebra and got 25%
let p be the price and w be the original weight
percent increase = ((p/0.8w - p/w)/(p/w))*100 = 25%

gracie · Answer

(p/4)/(p/5)=5/4=125%
25% increase in price per ounce
E

JeffTargetTestPrep · Answer

We are given that a certain candy manufacturer reduced the weight of Candy Bar M by 20 percent but left the price unchanged. If we let w = the original weight of the bar, the new weight is 0.8w = 4w/5. If we let p = the original price of the bar we know:

p/w = the original price per ounce of the bar

p/(4w/5) = 5p/4w = the new price per ounce of the bar

Finally we can determine the resulting percent increase in the price per bar due to the change:

/  x 100

p/4w x w/p x 100 = 1/4 x 100 = 25%

Answer: E

dabaobao · Answer

Let initial weight = 5
New price = 5 * 0.8 = 4

New Change in $/lb = ?
Original = $/5
New = $/4

Change = (New - Old)/Old = ($/4 - $/5)/$/5 = $/4 = 25%

ANSWER: E

KarishmaB · Answer

Price = Weight * Price per ounce

If weight is decreased by 20% (multiplied by 4/5) but overall price is kept same, then price per ounce must have been multiplied by (5/4).

Price = (\frac{4}{5}) * Weight * \frac{Price}{ounce} * (\frac{5}{4})

When you multiply something by 5/4, you are essentially increasing it by 25%.

Answer (E)

bumpbot · Answer

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A certain candy manufacturer reduced the weight of Candy Bar M by 20

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