Question

If A : B = 2 : 5 and A : C = 3 : 4, find: A : B : C.

Answer 1

To compare 3 ratios, the consequent of the first ratio and the antecedent of the 2^nd ratio must be made equal.

Given that A : B = 2 : 5 and A : C = 3 : 4

Interchanging the first ratio, we have,

B : A = 5 : 2 and A : C = 3 : 4

L.C.M of 2 and 3 is 6

`=>` B : A = 5 × 3 : 2 × 3 and A : C = 3 × 2 : 4 × 2

`=>` B : A = 15 : 6 and A : C = 6 : 8

`=>` B : A : C = 15 : 6 : 8

`=>` A : B : C = 6 : 15 : 8