If $a:b=3:4$ and $b:c=2:5$, then $a:b:c$ is:

Question

If $a:b=3:4$ and $b:c=2:5$, then $a:b:c$ is:

Option A

3:4:8

Option B — Correct answer

3:4:10

Correct choice.

Option C

6:8:15

Option D

8:10:15

Explanation

Make the middle term equal. Convert $a:b=3:4$ to $6:8$ and $b:c=2:5$ to $8:20$. So $a:b:c=6:8:20=3:4:10$.

Chapter Mock 2: Ratio, Proportion and Partnership