Set Probability

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Set Probability

by hai1 » Sun Mar 21, 2010 6:43 am
A= {2,3,4,5}; B={4,5, 6,7,8}

Total ways of choosing a pair from A and B or in other wordstotal ways of choosing one number from A and one number from B is 4*5=20.

Can we also find total ways of choosing one number from A and two numbers from B? Is it 4*4?
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by harshavardhanc » Sun Mar 21, 2010 6:56 am
hai1 wrote:A= {2,3,4,5}; B={4,5, 6,7,8}

Total ways of choosing a pair from A and B or in other wordstotal ways of choosing one number from A and one number from B is 4*5=20.

Can we also find total ways of choosing one number from A and two numbers from B? Is it 4*4?

it will be 4C1 * 5C2 = 4 * 10 = 40
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Harsha