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23 Jul 2017, 10:54
2
Top Contributor
15
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Difficulty:

35% (medium)

Question Stats:

75% (01:50) correct 25% (02:38) wrong based on 408 sessions

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23 Jul 2017, 16:36
4
2
carcass wrote:
Judy bought a quantity of pens in packages of 5 for $0.80 per package. She sold all of the pens in packages of 3 for$0.60 per package. If Judy's profit from the pens was $8.00, how many pens did she buy and sell? A. 40 B. 80 C. 100 D. 200 E. 400 It should be D. Cost price per pen =$0.80 / 5 = $0.16 or 16 cents. Sale price per pen =$0.60 / 3 = $0.20 or 20 cents. Profit per pen = 0.20 - 0.16 =$0.04 or 4 cents.

Profit = Profit per pen x number of pens

number of pens = Profit/profit per pen = 8/0.04 = 200
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##### General Discussion
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Judy bought a quantity of pens in packages of 5 for $0.80 per package [#permalink] ### Show Tags 23 Jul 2017, 16:59 carcass wrote: Judy bought a quantity of pens in packages of 5 for$0.80 per package. She sold all of the pens in packages of 3 for $0.60 per package. If Judy's profit from the pens was$8.00, how many pens did she buy and sell?

A. 40

B. 80

C. 100

D. 200

E. 400

carcass, you are a master of crafty language, and this one takes the prize.

The trap is in the second sentence: "She sold all of the pens in packages of 3 for $0.60 per package." That sentence does not mean that all the pens she sold were in packages of 3. In fact, coupled with the implication of answers that are not multiples of 15, the sentence means just the opposite; it means "not all the pens sold were in boxes of 3." A quantity that can be divided evenly into 5 per package and into 3 per package must be divisible by 15. None of the answer choices offers that possibility. So the pens Judy sold were not all in packages of 3. We have total profit. To get the number of pens, we need Judy's cost per pen and her sell price per pen. A package of five pens cost Judy 80 cents. $$\frac{80}{5}$$ = each pen cost 16 cents. A package of three pens sold for 60 cents.$$\frac{60}{3}$$ = each pen sold for 20 cents. Profit per pen is 20 - 16 = 4 cents' profit per pen. Total profit = (profit per pen) * (number N of pens sold)$8.00 = ($0.04)N $$\frac{8.00}{(0.04)}$$ = 200 Number of pens sold: 200 Answer D _________________ In the depths of winter, I finally learned that within me there lay an invincible summer. -- Albert Camus, "Return to Tipasa" Manager Joined: 24 Nov 2016 Posts: 152 Re: Judy bought a quantity of pens in packages of 5 for$0.80 per package  [#permalink]

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23 Jul 2017, 17:17
1
carcass wrote:
Judy bought a quantity of pens in packages of 5 for $0.80 per package. She sold all of the pens in packages of 3 for$0.60 per package. If Judy's profit from the pens was $8.00, how many pens did she buy and sell? A. 40 B. 80 C. 100 D. 200 E. 400 I. Cost per pen = 0.80/5 = (4/5)/5 = (4/5)*(1/5) = 4/25 = 16/100 = 0.16; II. Revenue per pen = 0.60/3 = 6/30 = 1/5 = 0.20; III. Profit per pen = Revenue per pen - Cost per pen = 0.20 - 0.16 = 0.04; IV. Total profit = profit per pen * quantity of pens: (8) = (0.04) * quantity, quantity = 8/0.04 = 800/4 = 200. Math Expert Joined: 02 Sep 2009 Posts: 48037 Re: Judy bought a quantity of pens in packages of 5 for$0.80 per package  [#permalink]

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24 Jul 2017, 00:48
2
carcass wrote:
Judy bought a quantity of pens in packages of 5 for $0.80 per package. She sold all of the pens in packages of 3 for$0.60 per package. If Judy's profit from the pens was $8.00, how many pens did she buy and sell? A. 40 B. 80 C. 100 D. 200 E. 400 Cost price: packages of 5 for$0.80 per package = $0.80/5 =$0.16 per pen.
Selling price: packages of 3 for $0.60 per package =$0.60/3 = $0.2 per pen. Profit = ¢4 per pen. Total profit = ¢800. The number of pens = 800/4 = 200. Answer: D. _________________ Manager Joined: 22 Nov 2016 Posts: 235 Location: United States Concentration: Leadership, Strategy GPA: 3.4 Re: Judy bought a quantity of pens in packages of 5 for$0.80 per package  [#permalink]

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24 Jul 2017, 09:21
1
$$\frac{x}{5} * (0.8) - \frac{x}{3}*(0.6)$$ = 8

$$\frac{2.4x - 3x}{15} = 8$$

x=200
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Re: Judy bought a quantity of pens in packages of 5 for $0.80 per package [#permalink] ### Show Tags 24 Jul 2017, 10:14 carcass wrote: Judy bought a quantity of pens in packages of 5 for$0.80 per package. She sold all of the pens in packages of 3 for $0.60 per package. If Judy's profit from the pens was$8.00, how many pens did she buy and sell?

A. 40

B. 80

C. 100

D. 200

E. 400

CP of a pen = $$\frac{80}{5} = 16$$

SP of a pen = $$\frac{60}{3} = 20$$

Profit = $$20-16 = 4$$, per pen.

Total profit = $$800$$, so number of pens = $$\frac{800}{4} = 200$$. Ans - D.
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Re: Judy bought a quantity of pens in packages of 5 for $0.80 per package [#permalink] ### Show Tags 26 Jul 2017, 16:37 1 carcass wrote: Judy bought a quantity of pens in packages of 5 for$0.80 per package. She sold all of the pens in packages of 3 for $0.60 per package. If Judy's profit from the pens was$8.00, how many pens did she buy and sell?

A. 40

B. 80

C. 100

D. 200

E. 400

We can let x = the number of pens she bought and sold. Since she bought the pens in packages of 5, she bought x/5 packages. Similarly, since she sold the pens in packages of 3, she sold x/3 packages. She bought the packages at $0.80 each and sold them at$0.60 each, and her profit is $8.00; thus, we can create the following equation: 0.60(x/3) - 0.80(x/5) = 8.00 60(x/3) - 80(x/5) = 800 20x - 16x = 800 4x = 800 x = 200 Answer: D _________________ Scott Woodbury-Stewart Founder and CEO GMAT Quant Self-Study Course 500+ lessons 3000+ practice problems 800+ HD solutions Manager Joined: 21 Jun 2017 Posts: 85 Judy bought a quantity of pens in packages of 5 for$0.80 per package  [#permalink]

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05 Sep 2017, 08:35
carcass wrote:
Judy bought a quantity of pens in packages of 5 for $0.80 per package. She sold all of the pens in packages of 3 for$0.60 per package. If Judy's profit from the pens was $8.00, how many pens did she buy and sell? A. 40 B. 80 C. 100 D. 200 E. 400 Profit = revenue - cost; Revenue = Sales price x quantity; cost = buy price x quantity profit = profit per individual pen x total number of pens Saleprice/pen = 0.60/3 = .20 cents per pen Buyprice/pen =0.80/5 = .16 cents per pen on the buy profit per pen = .20 - .16 = .04 cents profit per pen Profit = profit per pen x number of pens bought and sold 8.00 = .04 x N 200 = number of pens bought and sold bottom line with this one is to start out finding the cost of individual pen and the sale of individual pen. once you find the individual profit, set your variable, and divide from the total profit given. I got this one right, but idk, something weird with the way it is worded threw me off balance for a bit. Intern Joined: 16 Sep 2017 Posts: 3 Judy bought a quantity of pens in packages of 5 for$0.80 per package  [#permalink]

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22 Nov 2017, 23:59
Bunuel wrote:
Judy bought a quantity of pens in packages of 5 for $0.80 per package. She sold all of the pens in packages of 3 for$0.60 per package. If Judy's profit from the pens was $8.00, how many pens did she buy and sell? A. 40 B. 80 C. 100 D. 200 E. 400 Cost price: packages of 5 for$0.80 per package = $0.80/5 =$0.16 per pen.
Selling price: packages of 3 for $0.60 per package =$0.60/3 = $0.2 per pen. Profit = ¢4 per pen. Total profit = ¢800. The number of pens = 800/4 = 200. Answer: D. Bunuel ScottTargetTestPrep how is it possible to sell 200 pens in packages of 3? shouldn't the number of pens be a multiple of 3? Intern Joined: 16 Sep 2017 Posts: 3 Judy bought a quantity of pens in packages of 5 for$0.80 per package  [#permalink]

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Updated on: 25 Nov 2017, 07:37
mnshg wrote:
how is it possible to sell 200 pens in packages of 3? shouldn't the number of pens be a multiple of 3?

I was solving this Q under timed conditions.
I approached the problem by concluding that the answer must a multiple of 3 and 5, but couldn't find such a number in the answer choices. So I got tensed about the time wasted and then couldn't solve it any further.

Originally posted by mnshg on 25 Nov 2017, 07:26.
Last edited by mnshg on 25 Nov 2017, 07:37, edited 1 time in total.
Math Expert
Joined: 02 Aug 2009
Posts: 6556

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15 Dec 2017, 10:42
carcass wrote:
Judy bought a quantity of pens in packages of 5 for $0.80 per package. She sold all of the pens in packages of 3 for$0.60 per package. If Judy's profit from the pens was $8.00, how many pens did she buy and sell? A. 40 B. 80 C. 100 D. 200 E. 400 --> cost price of 5 pens is 0.8 => 15 would cost 2.4$
---> selling price of 3 pens is 0.8 => 15 would cost 3.0$Net profit on 15 pens is 0.6$
0.6 $profit on 15 pens 8.0$ profit on how many pens = (8 *15)/(0.6) = (800* 15)/(60) = (800/4)= 200.

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