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7:43 PM
@gateprep are you still around and looking for help with this problem?
 
8:17 PM
yes
I am
Please solve it step by step
 
9:11 PM
I'm barely learning that stuff as well, I only hope that maybe together we can shed some light onto this example
I see that this is a type of combinatorics mixed up with probabilities
at the denaminator you will have all possible cases for, P(S)
at the numerator it will be cases when non of the blood types repeat. This sounds like a permutation
 

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