Question

a:b = 4:5 and b:c = 2:5 find a:b:c

Answer 1

a/b=4/5*2/2
b/c=2/5*5/5
=a/b=8/10
=b/c=10/25
so,
a:b:c=8:10:25

Answer 2

A:B=4:5
B:C=2:5
therefore, A:B:C=4*2:5*2:5*5
                          =8:10:25
answer=8:10:25

(*)means multiply.