C - 8/15c = 1/3 2/5d + 3/10d - 2/15d = 1/6

Question

C - 8/15c = 1/3

2/5d + 3/10d - 2/15d = 1/6

Answer 1

С-8/15с=1/3
7/15с=1/3
с=1/3:7/15
с=1/3*15/7
с=5/7

12/30d+9/30d-4/30d=1/6
17/30d=1/6
d=1/6:17/30
d=1/6*30/17
d=5/17