Question

if A:B = 2:3, B:C= 3:4 and C:D=4:5. find the ratio between A and D

Answer 1

first,  make it in upon fraction  

2/3 3/4 4/5

3 will cutted from 3
4 will cutted from 4
so, the answer will come 2/5 = 2:5

Answer 2

A:B=2:3
B:C=3:4                     [Given]
C:D=4:5
Solution:
A:B=2:3
B:C=3:4
Since ratio of B is same in both cases,
Ratio of A:C=2:4
Ratio of A:C=2/4=1/2
Ratio of A:C=1:2

A:C=1:2
C:D=4:5
Make C equal in both cases,
A:C=1×2:2×2
C:D=4:5
A:C=2:4  ···········(i)
C:D=4:5  ···········(ii)
Since C is equal in both cases,
A:D=2:5