Set Theory PS

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Set Theory PS

by rabab » Thu Sep 25, 2008 7:27 am
Someone pls. help me out with this PS--

In a certain production lot 40% of the toys are red and remaining toys are green. Half of the toys are small and half are large. If 10% of the red toys are small, 40 toys are green and large. How many of the toys are red and large?
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by txeconomist » Thu Sep 25, 2008 10:01 am
Re:"In a certain production lot 40% of the toys are red and remaining toys are green. Half of the toys are small and half are large. If 10% of the red toys are small, 40 toys are green and large. How many of the toys are red and large?"

Is this problem copied correctly?

The given info implies that Small-Red equal 4% of the total (10% of 40%). If that it the case then the Big-Red equals 36% of the total.

Further if Big-Red (36%) + Big-Green = 50% of total, then Big-Green is equal to 14% which we are told is 40. But that doesn’t really make sense cause then the total would be 285.7…

I could be wrong though

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Re: Set Theory PS

by Morgoth » Thu Sep 25, 2008 10:20 am
rabab wrote:Someone pls. help me out with this PS--

In a certain production lot 40% of the toys are red and remaining toys are green. Half of the toys are small and half are large. If 10% of the red toys are small, 40 toys are green and large. How many of the toys are red and large?
40% = red
60% = green

50% = large
50% = small

10% = red + small
30% = red + large

20% = green + large
40% = green + small

let x be total no. of toys

20% x = 40
x = 200

30% = red + large
200 * 30% = 60

Thus, 60 is the answer.

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by txeconomist » Thu Sep 25, 2008 10:26 am
that is what i was getting at... the original says 10% of the red toys are small....not that 10% of the toys are red and small.

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Re: Set Theory PS

by rabab » Thu Sep 25, 2008 11:01 am
Morgoth wrote:30% = red + large

20% = green + large
40% = green + small
I am sorry. But could you pls explain these few lines for me?

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by rabab » Thu Sep 25, 2008 11:10 am
Never mind. I got it! Just confused the R+L part! Thanks a lot! :D

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Re: Set Theory PS

by 4meonly » Fri Sep 26, 2008 7:10 am
I dont understand Morgoth's logic

Somebody, pls, explain me...
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by txeconomist » Fri Sep 26, 2008 11:16 am
4meonly,

the problem is either incorrectly copied or its a bad problem. The problem states that 10% of the red toys are small...but, it should say 10% of the toys are red and small.

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by rabab » Tue Sep 30, 2008 7:03 am
i think 10% of the toys red + small. i copied the problem just as i got it. i think this problem came in the arco's gmat prep book.

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by nikhilagrawal » Tue Sep 30, 2008 1:26 pm
Rabab...

Is the answer 36 ??

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by rabab » Tue Sep 30, 2008 9:39 pm
nikhilagrawal wrote:Rabab...

Is the answer 36 ??
No it's 60.