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Car probability

by GmatKiss » Thu May 24, 2012 10:52 pm
The Carson family will purchase three used cars. There are two models of cars available, Model A and Model B, each of which is available in four colors: blue, black, red, and green. How many different combinations of three cars can the Carsons select if all the cars are to be different colors?
24
32
48
60
192
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by Anurag@Gurome » Thu May 24, 2012 10:55 pm
GmatKiss wrote:The Carson family will purchase three used cars. There are two models of cars available, Model A and Model B, each of which is available in four colors: blue, black, red, and green. How many different combinations of three cars can the Carsons select if all the cars are to be different colors?
24
32
48
60
192
1st car can be selected from 8 cars in 8 ways
2nd car can be selected from 6 cars in 6 ways
3rd car can be selected from 4 cars in 4 ways
Hence, # of possible combinations = (8 * 6 * 4)/3! = 32

The correct answer is B.
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by kullayappayenugula » Thu May 24, 2012 11:24 pm
hi Anurag,


can you please explain why we have to divide by 3! below??

Hence, # of possible combinations = (8 * 6 * 4)/3!
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by Anurag@Gurome » Fri May 25, 2012 12:07 am
kullayappayenugula wrote:hi Anurag,


can you please explain why we have to divide by 3! below??

Hence, # of possible combinations = (8 * 6 * 4)/3!
We divided by 3! because the order is not fixed here.
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