Question

2.A race is designed such that the person who completes twenty rounds of the circular field track of50 meter radius first wins the race. Irrespective of the time taken everybody has completed the race.A, B and C were among the participants. A has overtaken B (for the first time) after A completed4th of his 10th round and B has overtaken C (for the first time) in exactly the middle of5B's 12th round. If C has taken 30 minutes to complete the race then what was the speed ofA? It is assumed that the running speed of participants remains constant throughout the race.[m/m = meter/minute]1) 236 m/m2) 246 m/m 3) 256 m/m 4) 266 m/m​

Answer 1

Given that : Radius of circle =r=50 m

Speed of man =12 km/hr =

3600

12×1000

=3.33 m/s

Distance travelled in one round =2πr=314m

⇒ Distance travelled in ten rounds =3140 m

Time taken = Distance÷Speed =

3.33

3140

=942 seconds

∴ Time taken =15 mins 42 seconds