nilai a dan b adalah

6/a = (6+4)/15
6/a = 10/15
a = 6 × 15 ÷ 10
a = 9


9/15 = 12/(12+b)
9 ( 12+b ) = 15 × 12
108 + 9b = 180
9b = 180 - 108
9b = 72
b = 72 ÷ 9
b = 8


Jadi a = 9 dan b = 8