Probability---clothing combination

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by Everest » Thu Jan 27, 2011 10:22 pm
Total number of possibilities are 72 possibilities ( 8*9) (shirts * pants)
No. of combinations are not allowed are 6 possibilities (2 * 3) ( 2 shirts and 3 pants)


Therefor (72 - 6) , 66 combinations are possible.



IMO B

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by pesfunk » Fri Jan 28, 2011 6:11 am
Barbara has 8 shirts and 9 pants
she doesn't wear 2 specific shirts with 3 specific pants

This means, ideally she has 6 shirts and 6 pants to chose from.

The combination in this case would be 6x6 = 36

Whatz the OA ?

Everest wrote:Total number of possibilities are 72 possibilities ( 8*9) (shirts * pants)
No. of combinations are not allowed are 6 possibilities (2 * 3) ( 2 shirts and 3 pants)


Therefor (72 - 6) , 66 combinations are possible.



IMO B
[spoiler][/spoiler]

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by prachich1987 » Fri Jan 28, 2011 6:33 am
pesfunk wrote:Barbara has 8 shirts and 9 pants
she doesn't wear 2 specific shirts with 3 specific pants

This means, ideally she has 6 shirts and 6 pants to chose from.

The combination in this case would be 6x6 = 36

Whatz the OA ?

Everest wrote:Total number of possibilities are 72 possibilities ( 8*9) (shirts * pants)
No. of combinations are not allowed are 6 possibilities (2 * 3) ( 2 shirts and 3 pants)


Therefor (72 - 6) , 66 combinations are possible.



IMO B
[spoiler][/spoiler]
Barbara doesn't wear 2 specific shirts with 3 specific pants
It doesn't mean that she never wears these 2 shirts & 3 pants
She can wear one of these two shirts with one of the remaining 6 pants

The OA is B

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by pesfunk » Fri Jan 28, 2011 6:38 am
Oops...overlooked the WITH

2 specific shirts with 3 specific pants
prachich1987 wrote:
pesfunk wrote:Barbara has 8 shirts and 9 pants
she doesn't wear 2 specific shirts with 3 specific pants

This means, ideally she has 6 shirts and 6 pants to chose from.

The combination in this case would be 6x6 = 36

Whatz the OA ?

Everest wrote:Total number of possibilities are 72 possibilities ( 8*9) (shirts * pants)
No. of combinations are not allowed are 6 possibilities (2 * 3) ( 2 shirts and 3 pants)


Therefor (72 - 6) , 66 combinations are possible.



IMO B
[spoiler][/spoiler]
Barbara doesn't wear 2 specific shirts with 3 specific pants
It doesn't mean that she never wears these 2 shirts & 3 pants
She can wear one of these two shirts with one of the remaining 6 pants

The OA is B

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by arora007 » Fri Jan 28, 2011 6:39 am
whenever you have a negative connonation... prefer the 1 - x approach to solve.

over here we see the "doesn't"

so (8*9 - 2*3) = 72-6 = 66

B is the answer
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