A and B start from ab at the same time and run in opposite directions. The speed ratio of a and B is 5:4 when they start. After meeting, a speeds up by 20% and B decelerates by 25%. Continue to drive When a arrives at B, B is 60kg away from the midpoint of AB, and ab is the whole journey

A and B start from ab at the same time and run in opposite directions. The speed ratio of a and B is 5:4 when they start. After meeting, a speeds up by 20% and B decelerates by 25%. Continue to drive When a arrives at B, B is 60kg away from the midpoint of AB, and ab is the whole journey

In the whole process, unit 1: when meeting, a drove 5 / 9, B drove 4 / 9, a accelerated 20%, B decelerated 25%; their speed ratio became: [5 × (1 + 20%)]: [4 × (1-25%)] = 2:1, that is, B's speed was 1 / 2 of a's speed, after a drove 4 / 9, then B drove 4 / 9 × 1 / 2 = 2 / 9, B drove 4 / 9 + 2

After the first meeting, a's speed increased by 25%, and B's speed increased by 20%. So when B arrives at a, a is still 15 kilometers away from B, and the distance between a and B is calculated

The distance between the two places is x km
At the first meeting, the distance traveled by Party A and Party B was 4x / 9 and 5x / 9 respectively
After the first encounter, a's speed increased by 25%, B's speed increased by 20%,
Then the velocity ratio is 4 (1 + 25%): 5 (1 + 20%) = 5:6
The distance ratio after the first meeting is 5:6
That is (5x / 9-15) △ 4x / 9 = 5:6
x=81
The distance between the two places is 81 km