If d : e = 4 : 3 and e : f = 7 : 8, then find d : e : f?

28 : 21 : 24

28 : 21 : 11

11 : 21 : 24

None of these

We are given:

d : e = 4 : 3

e : f = 7 : 8

To combine them, make the value of e the same in both ratios.

LCM of 3 and 7 = 21

So,

d : e = 4×7 : 3×7 = 28 : 21

e : f = 7×3 : 8×3 = 21 : 24

Now combine:

d : e : f = 28 : 21 : 24