In a 900 meters race, A gives B a start of 150 meters and defeats him by 50 seconds. If the speed of A is 4.5 m/sec, then speed of B is:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 3 m/sec
A runs the full 900 m. With a start of 150 m, B runs only 900 − 150 = 750 m.
\( \displaystyle \text{Time of A}=\frac{900}{4.5}=200\text{ s} \)
A defeats B by 50 seconds, so B takes 50 s more:
\( \displaystyle \text{Time of B}=200+50=250\text{ s} \)
\( \displaystyle \text{Speed of B}=\frac{750}{250}=3\text{ m/sec} \)
CBSE Applied Mathematics (Class XII):
Races and Games
