Respostas

2014-05-17T20:34:00-03:00
N(AUB) = N(A) + N(B) - N(A∩B)
N(A) = 20 // N(AUB) = 60 // N(
A∩B) = 12
60 = 20 + N(B) - 12
N(B) = 60-20+12
N(B) = 52
O conjunto B tem 52 elementos.
1 5 1