Thinking: Suppose A is fast and B is slow. The sum of the speeds of Party A and Party B: 250÷ 10 = 25m/ sec for 50 seconds * * Two people walk: 50÷ 10=5 laps, and Party A walks 1 lap more than Party B for 50 seconds, that is, the speed difference between Party A and Party B is 250 \
A speed: (25+5) ÷ 2 = 15m/s, and B speed 25-15 =10m/s. ..