Runner A completes a 1-kilometer race in 4.5 minutes, whereas runner B finishes the same race in 5 minutes. What distance advantage should A give B at the start so that they both finish simultaneously?

Explanation

Since A runs 1 km in 4.5 minutes and B in 5 minutes, the time difference is 30 seconds. B's speed is 1000 meters per 5 minutes, so in 30 seconds B covers (1000 × 30) / 300 = 100 meters. Therefore, A should give B a 100-meter head start for the race to end in a tie.