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ajay.05
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Mentor note: Moved from a non-HW forum section, so missing the HW template
When I was attending probability class, my math teacher said me that in the problems involving Case 1 'and' Case 2, I have to multiply probability of Case 1 and Case 2, while in the case of Case 1 'or' Case 2, I have to add probability of Case 1 and Case 2. I didn't get any valid reason from my Math teacher for this statement. Recently, when I was Studying Combinatorics, I cam across the same thing. I can give an Example from that...
"What is the number of ways of choosing 4 cards from a pack of playing cards, such that
1)Four Cards of the same suit
2)Four Cards belonging to different suits"
For the first question, it means 13C4 or 13C4 or 13C4 or 13C4, that is 13C4+13C4+13C4+13C4
For the second question, it means 13C1 and 13C1 and 13C1 and 13C1, that is 13C1*13C1*13C1*13C1
Can anybody please explain this to me? What do actually these and/or things mean?
Thanks in Advance:)
When I was attending probability class, my math teacher said me that in the problems involving Case 1 'and' Case 2, I have to multiply probability of Case 1 and Case 2, while in the case of Case 1 'or' Case 2, I have to add probability of Case 1 and Case 2. I didn't get any valid reason from my Math teacher for this statement. Recently, when I was Studying Combinatorics, I cam across the same thing. I can give an Example from that...
"What is the number of ways of choosing 4 cards from a pack of playing cards, such that
1)Four Cards of the same suit
2)Four Cards belonging to different suits"
For the first question, it means 13C4 or 13C4 or 13C4 or 13C4, that is 13C4+13C4+13C4+13C4
For the second question, it means 13C1 and 13C1 and 13C1 and 13C1, that is 13C1*13C1*13C1*13C1
Can anybody please explain this to me? What do actually these and/or things mean?
Thanks in Advance:)
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