Question

When she was in year 8,Sarah could run 800 meters in 3 minutes and 20 seconds.

Three years later, when she was in year 11, she could run 800 meters in 2 minutes and 40 seconds.

Find the percentage improvement in her time and show your working out.

Answer 1

125% improvement

Explanation:

3min 20sec = 200sec

2min 40sec = 160sec

800meters/ 200sec = 4 meters per second

800meters/ 160sec = 5 meters per second

5/4 : x/100

4x = 500

x = 125