Answer:
a:b:c = 6:15:20
Step-by-step explanation:
Given;
[tex]\frac{a}{b} = \frac{2}{5} \ \ and \ \ \frac{b}{c} = \frac{3}{4}[/tex]
a:b:c is determined as follows;
a:b = 2:5 and b:c = 3:4
find the common factors in both equation = b = 5 and 3
Then, multiply the first equation by 3 and second equation by 5, so that value of b in both equations will be the same.
a:b = 6:15
b:c = 15:20
Thus, a:b:c = 6:15:20
