The points A , B , C, D and E are located on a straight line in that order. The distance from A to E is 20cm. Te distance from A to D is 15cm. The distance from B to E is 10com. C is halfway between B and D. What is the distance from B to C?

Answer 1

5 cm

Answer 2

First you draw a straight line (measured at 20 cm) with A at the beginning and E at the end. Then you know A to D is 15 cm so you can mark D. Next you measure from B to E. You know it is 10 cm so you can mark B. Since C is half-way between B and D, you can get the distance from B to C.

10 5 5
A----------B-----D-----E