A store bought 5 dozen lamps at $30 per dozen and sold them

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A store bought 5 dozen lamps at $30 per dozen and sold them all at $15 per lamp. The profit on each lamp was what percent of its selling price?

A. 20%

B. 50%

C. \(83 \frac{1}{3}\)%

D. 100%

E. 500%




OA C

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by GMATGuruNY » Wed Dec 25, 2019 4:42 am
BTGmoderatorDC wrote:A store bought 5 dozen lamps at $30 per dozen and sold them all at $15 per lamp. The profit on each lamp was what percent of its selling price?

A. 20%

B. 50%

C. \(83 \frac{1}{3}\)%

D. 100%

E. 500%
Cost per lamp = (cost per dozen)/(number of lamps in a dozen) = 30/12 = 5/2 = $2.50.
Profit per lamp = (selling price per lamp) - (cost per lamp) = 15 - 2.5 = $12.50.
Profit as a percentage of selling price = (profit)/(selling price)* 100 = (12.5/15) * 100 = (125/150) * 100 = (5/6)(100) = 83â…“%

The correct answer is C.
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by SampathKp » Wed Dec 25, 2019 3:44 pm
BTGmoderatorDC wrote:A store bought 5 dozen lamps at $30 per dozen and sold them all at $15 per lamp. The profit on each lamp was what percent of its selling price?

A. 20%

B. 50%

C. \(83 \frac{1}{3}\)%

D. 100%

E. 500%


1 dozen lamps = 12 lamps
1 dozen laps cost = $30
1 lamp cost $30/12 = $ 2.5

Each lamp was sold for $15. Profit on each lamp = $15- $2.5 = $12.50

Profit on each lamp is what % of selling price of each lamp = $12.50/$15 *100 = 83.3%

Answer is C

OA C

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by Scott@TargetTestPrep » Sat Dec 28, 2019 8:11 pm
BTGmoderatorDC wrote:A store bought 5 dozen lamps at $30 per dozen and sold them all at $15 per lamp. The profit on each lamp was what percent of its selling price?

A. 20%

B. 50%

C. \(83 \frac{1}{3}\)%

D. 100%

E. 500%

OA C

Source: Official Guide
The cost per lamp is 30/12 = 2.5.

The profit per lamp is 15 - 2.5 = 12.5.

Thus, the profit as a percent of selling price is:

12.5/15 = 25/30 = 5/6 = 83 1/3 %

Answer: C

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