A bus and a car go from a place to B place at the same time. The car will return immediately after arriving at B place. The speed will be increased by 20% when returning and 1.5 hours after departure The two cars meet for the first time. When the bus arrives at the second place, the car is still 20% away from the first place? We need it now

A bus and a car go from a place to B place at the same time. The car will return immediately after arriving at B place. The speed will be increased by 20% when returning and 1.5 hours after departure The two cars meet for the first time. When the bus arrives at the second place, the car is still 20% away from the first place? We need it now

When the car goes V, return 1.2V. Bus speed v. S. desire s / V + S / 1.2V
Lie equation: S = 1.5V + (1.5-s / V) * 1.2V
S/V =s/v +（s-0.2s)/1.2v
The solution is s / V + S / 1.2V = 2.25h

It takes two hours for a car to drive from a to B, and four hours for a truck to drive from B to a. the two cars start from two places at 8:30 a.m., and meet each other on the way after a few hours? When and when did you meet?

1 △ (12 + 14) = 1 △ 34 = 1 × 43 = 113 (hours); 113 hours = 1 hour and 20 minutes; 8:30 + 1:20 = 9:50 minutes; a: after 113 hours, we met on the way, and it was 9:50 minutes

There is a pile of 30 tons of coal, 3 tons for small trucks and 6 tons for large trucks

Five times
30 (3 × 2) = 5 (Times)
Answer: five times to transport coal