Question

Si A { x/x es múltiplo de 4 y 56<x<82}
hallar n( A)

Answer 1

56 < X < 82  , donde X = 4n
entonces: 56 <  4n < 82 ⇒ 28 < 2n < 41
donde n = 15, 16, 17, 18, 19, 20
X = 15(4) = 60
X = 16(4) = 64 .......

X = 60, 64, 68, 72, 76, 80

ENTONCES n(A) = 6

suerte XD