Pke cara Yaa Please

91. n(A gabungan B)=n(A)+n(B) -n(AirisanB)
=28+19 - 12
=35

92. pakai rumus yang atas tadi
32 =21 + 18 - x
32 = 39-x
x = 7

93. 45 = 30+ x - 8
45 = 22+x
x = 23