Permutation and combinations

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Source: — Problem Solving |

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by ace_gre » Fri Jan 15, 2010 6:03 pm
Hi, Please post the answer choices, as this makes it easier to solve..

Here is my approach.

No. of ways for selecting (>= 2 JKQ) = Total ways of selecting 3 cards - # of ways of selecting (<2 JKQ) = Total - (zero JKQ) -P( one JKQ)

Total ways of selecting 3 cards = 52C3
No. of JKQ = 12
Non JKQ cards = 52-12 = 40
Ways of selecting 0 JKQ = 40C3
Ways of selecting 1 JKQ = 12C1 * 40C2

Ways to select >= two JKQ ==> 52C3 - 40C3- 12* 40C2

Is there anything along these lines in the choices?

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by hemanthquartz1 » Fri Jan 15, 2010 7:18 pm
You are right. Answer is 2860 :)

Thanks