If A:B:C =1:3:5 and C:D = 2:5 then A:B:C:D is equal to:
Common terms in A:B:C and C:D is C.
Ratio values of C in both the ratios are 5 and 2 respectively
LCM of 5 and 2 is 10
In first ratio A:B:C = 1:3:5, to transform C value from 5 to 10, you have to multiply all the terms by 2
Therefore, A:B:C = 1x2:3x2:5x2 = 2:6:10
In second ratio C:D = 2:5, to transform C value from 2 to 10, you have to multiply all the terms by 5
Therefore, C:D = 2x5:5x5 = 10:25
If you combine both the transformed ratios by writing C's value only once, you will get
A:B:C:D = 2:6:10:25