The speed of passenger cars on expressways is usually several kilometers per hour

The speed of passenger cars on expressways is usually several kilometers per hour

The carts are generally 90-110 km long

The speed of car a on the highway is 100 km / h, and that of car B is 120 km / h. at this moment, car a is 80 km in front of car B, and car a will continue to drive forward after refueling and parking for 10 minutes. How long will it take car B to catch up with car a at least from 80 km away?

10 minutes = 1 / 6 hour
10 minutes B car (1 / 6) × 120 = 20 (km)
Time required for B to catch up with a: (80-20) / (120-100) + 10 minutes
=3 (hours) 10 minutes

A car from a to B, the first 1 / 3 of the road for the ordinary highway, the rest of the road for the highway
A car from a to B, the first 1 / 3 of the road for ordinary highway, the rest of the road for highway. It is known that the speed of a car is 60km / h on an ordinary highway and 100km / h on an expressway. It takes 2.2 hours for a car to travel from a to B. how many kilometers are there from a to B

1 set the distance between a and B as m km, m multiplied by 1 / 3 = 1 / 3M is the distance of ordinary highway, m multiplied by (1-1 / 3) = 2 / 3M is the distance of expressway, 2 time multiplied by speed = distance, in other words, time = distance / speed, driving time of ordinary highway = 1 / 3M divided by 60km / h = m / 180, high speed = 2 / 3M divided by 100km /