If a:b=1:3, b:c=5:7 then what is the value of a:b:c?
A
3:5:7
B
5:9:15
C
5:15:21
D
4:13:24
Correct Answer: 5:15:21
a:b = 1:3 *5 = 5:15b:c = 5:7 *3 = 15:21So, a:b:c = 5:15:21 (Ans)