Questions from GMATPrep-2

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Questions from GMATPrep-2

by rabab » Fri Nov 14, 2008 6:02 am
1. A certain restaurant offers 6 kinds of cheese and 2 kinds of fruits for its dessert platter. If each dessert platter contains an equal no. of kinds of cheese and kinds of fruits how many different dessert platters could the restaurant offer?

a) 8, b)12, c)15, d)21, e)27

2. Machine A produces pencils at a constant rate of 9,000 pencils per hour, and machine B produces pencils at a constant rate of 7,000 pencils per hour. If the two machines together must produce 100,000 pencils and if each machine can operate for at most 8 hours, what is the least amount of time, in hours, that machine B must operate?

a) 4, b) 8, c) 5, d) 6, e)7
Source: — Problem Solving |

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by mals24 » Fri Nov 14, 2008 6:29 am
The first one has been solved in the link below

https://www.beatthegmat.com/probability-t22672.html

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by mals24 » Fri Nov 14, 2008 6:50 am
In order to minimize one factor you maximize the other.
Hence in order to min B you max A

Max pens A can produce in 8 hours = 8*9000 = 72,000

Total pens to be produced = 100,000

Hence B needs to produce the remaining 100,000-72,000 = 28,000 pens

Total time B takes to produce 28,000 pens = 28,000/7000 = 4 hours

Hence the answer should be A.

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by rabab » Fri Nov 14, 2008 7:28 am
Thanks a LOT mals24. Those were some wonderful solutions!