Question

Patricia roller skates 0.50 kilometers, straight north to the library. Then she walks 0.25 kilometers to her friend's house, which is straight north of the library. What is Patricia's displacement?

Answer 1

The answer is: 0.75 km, north

Answer 2

The answer is 0.75 kilometers.

Displacement is the shortest distance between the initial and the final point. But, Patricia roller skates in the straight line, so her displacement is the distance between the initial and the final point:

0.50 km + 0.25 km = 0.75 km.

Therefore, Patricia's displacement is 0.75 kilometers.