Hitunglah nilai a, b, c, d dan e pada gambar di bawah ini.

A.

9 / (9+a) = 12 / 20
12(9+a) = 9×20
108 + 12a = 180
12a = 180-108
12a = 72
a = 6

12/(20+b) = 9/21
9(20+b) = 12×21
180 + 9b = 252
9b = 252 - 180
9b = 72
b = 8


B.
c/12 = 15/9
c = ( 12 × 15 ) ÷ 9 = 20

C.
12/d =18/8
d = (12 × 8) ÷ 18 = 16/3

e/6 = 18/8
e = ( 18 × 6 ) ÷ 8 = 27/2

D.
15/d =12/8
d= (15 × 8) ÷12 = 10

e/9 =8/12
e = (9×8)÷12 = 6