Question

If n(A)=20, n(B) = 15 n(AUB)= 25, Then find n(ANB)
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Answer 1

Step-by-step explanation:

$n(a) = 20 \: \: \: \: \: \: \: \: n(b) = 15 \: \: \: \: \: \: \: \: \: \: n(a \: \: \: union \: \: b) = 25 \\ \\ 25 = 20 + 15 - n(a \: \: \: \: and \: \: \: \: \: b) \\ \\ therefore \: \: \: \: n(a \: \: \: \: \: and \: \: \: \: \: b) = 35 - 25 \\ \\ = 10.$

n(a intersection b) = 10.

Answer 2

Answer:

n(A)= 20

n(B)= 15

n(AUB)= 25

To find:

n(AnB)

Sol.

From formula:

n(a)+n(b)-n(aUb)=n(AnB)

>>20+15-25

>>35-15

>>20

Therefore n( AnB) is 20