Question

If (a) =15,n(aub)=29,n(anb)=7 find n(b)

Answer 1

Given,

n(a) = 15

n(a u b) = 29

n(a n B) = 7

n(b) = ???

We know a formula that ;

→ n(a u b) = n(a) + n(b) - n(a n b)

→ 29 = 15 + n(b) - 7

→ n(b) = 29 - 8

So, n(b) = 21 ____________ (Ans.)

Hope it helps...

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