Point C divides line segment AB so that

AC/AB = 1/3. If AC = 5 cm, what is AB?

1 answer

Let AB = x.
Given that AC/AB = 1/3, we can write:
5/x = 1/3.

Cross-multiplying, we get:
3 * 5 = x * 1.

15 = x.

Therefore, AB = 15 cm.