Questions from GMATPrep

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Questions from GMATPrep

by bkobilov » Fri Oct 08, 2010 5:43 am
Please help with these problems.

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 number of kinds of cheese and kinds of fruit, how many different dessert platters could the restaurant offer?

8
12
15
21
27

OA: E

2. A certain car averages 25 miles per gallon of gasoline in city and 40 miles per gallon on highway. Which of the following is closest to the number of miles per gallon when it is driven 10 miles in the city and then 50 miles on the highway?

28
30
33
36
38

OA: D

3. A certain city with a population of 132,000 is to be divided into 11 voting districts, and no district is to have a population that is more than 10 percent greater than the population of any other district. What is the min possible population that the least populated disstrict could have?

10700
10800
10900
11000
11100

OA: D
Source: — Problem Solving |

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by kmittal82 » Fri Oct 08, 2010 5:53 am
Ans1)

You can get either 1cheese+1fruit, or 2 cheese and 2 fruits

#ways to select 1cheese and 1fruit = 6x2 = 12
#ways to select 2cheese and 2 fruits = 6C2 x 1 = 15

Total ways = 12+15 = 27

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by kmittal82 » Fri Oct 08, 2010 5:58 am
Ans2)

10 miles in the city = 10/25 gallons = 2/5 = 0.4
50miles on highway = 50/40 gallons = 5/4

total gallons used = 2/5 + 5/4 = 33/20

total miles driven = 60

Total mpg = 60x20/33 which is approximately 36

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by kmittal82 » Fri Oct 08, 2010 6:08 am
Ans3)

Let the population of any 1 city = x

The max population of any other city can be 1.1x

Lets assume all the other cities are of population 1.1x, which would mean population x would be the minimum

thus, x + 10(1.1x) = 132,000

12x = 132,000

x = 11000

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by bkobilov » Fri Oct 08, 2010 6:22 am
kmittal82, thanks so much