If A : B = 3 : 5 and B : C = 4 : 7, then the value of A: B: C is:

Correct option is D

Given:
A : B = 3 : 5 and B : C = 4 : 7
Formula Used:
To find the combined ratio A : B : C , make the common term B equal in both ratios by finding the least common multiple (LCM) of the values of B.
Solution:
We have A : B = 3 : 5 and B : C = 4 : 7 .
First, find the LCM of 5 and 4, which is 20.
Convert the ratios so that B has the same value in both:
A : B = $$3 \times 4 : 5 \times 4 = 12 : 20$$​​
B : C = $$4 \times 5 : 7 \times 5 = 20 : 35$$​​
Therefore, the combined ratio A : B : C = 12 : 20 : 35 .