A and B race around the lake in the same direction, 400 meters a week, B walk 80 meters per minute, a's speed is 5 / 4 times of B's, a is 100 meters in front of B, how many minutes do two meet

A and B race around the lake in the same direction, 400 meters a week, B walk 80 meters per minute, a's speed is 5 / 4 times of B's, a is 100 meters in front of B, how many minutes do two meet

If B walks 80 meters per minute and a's speed is 5 / 4 times that of B, then a walks 80 × (5 / 4) = 100 meters per minute;
A is 100 meters ahead of B. because a is faster than B, a needs to chase 400-100 = 300 meters to meet B;
Can get: after 300 (100-80) = 15 minutes, two people meet

A and B are running on a 400m long circular track. A's speed is 360m / min, B's speed is 240m / min
A and B are running on a 400m long circular track. A's speed is 360m / min, B's speed is 240m / min
1. How many laps did they run in the same direction at the same time?
2. Two people at the same time reverse run, ask a few seconds later two people meet for the first time
Equation, one variable one time

(1) When we meet for the first time, it means that a exceeds B by one lap, that is, with the same time, a runs more than 400 meters. Suppose the time is x, then 360x-240x = 400, and the solution is x = 10 / 3. So, a runs (10 / 3) * 360 / 400 = 3 laps, B runs (10 / 3) * 240 / 400 = 2 laps, so two people run 2 + 3 = 5 laps

A and B race along the playground. It is known that a circle of the playground is 400 meters. A's speed is 100 meters per minute, and B's speed is 80 meters per minute
(1) How many hours did it take for the two to meet for the first time? How many days did they each walk?
(2) How many minutes will it take for the second meeting

(1) Let the first meeting take X minutes, 100x = 400 + 80x2x = 400X = 20, that is: 20 minutes = 1 / 3 hour, two people meet for the first time. At this time, a walks 100 × 20 / 400 = 5 (circle), B walks 80 × 20 / 400 = 4 (circle) (2) let the second meeting take y minutes, 100 (y-20) = 400 + 80 (y-20) 100y-2000 = 400

Party A and Party B practice walking race on the 400 meter track of the playground. They start at the same time. Party A is behind Party B when they start. Six minutes after starting, Party A surpasses Party B for the first time, and Party B starts at the same time
Party A and Party B practice race walking on the 400 meter track of the playground. They set out at the same time. When they set out, Party A was behind Party B. after 6 minutes, Party A surpassed Party B for the first time, and Party A surpassed Party B for the second time in 22 minutes. Suppose that the speed of the two people remains the same, ask: how many meters is a behind B when starting?

6 minutes to 22 minutes, a total of 16 minutes, 22-6 = 16 minutes
That is to say, the distance for a to catch up with B in 16 minutes is 400 meters
Catch up with 400 / 16 = 25m per minute
At the beginning, it took 6 minutes to catch up with 25 × 6 = 150 meters