Question 1119610
let a and b be two finite sets such that n(A)=15,n(B)=10 and n(AUB)=13 find n(AnB).
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Ans: n(A and B) = n(A)+n(B)-n(A or B)
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Ans: n(A and B) = 15 + 10 - 13 =  12
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Cheers,
Stan H.
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