2017 · Q23
In a 100 m race, A runs at a speed of 5/3 m/s. If A gives a start of 4 m to B and still beats him by 12 seconds, what is the speed of B ?
Elementary MathematicsTime, Speed and Distance
- A5/4 m/s
- B7/5 m/s
- C4/3 m/s
- D6/5 m/s
Explanation
A's 100 m at 5/3 m/s takes 60 s. B runs 100 − 4 = 96 m in 60 + 12 = 72 s, so B's speed = 96/72 = 4/3 m/s: option C.