The expressway from Shijiazhuang to Chengde is 546 kilometers long. The Honghong family drove from Shijiazhuang to Chengde to visit the summer resort. If they drive an average of 78 kilometers per hour and leave at 8 am, when will they arrive?
3. A bus starts from Zhang Cun. If you drive at a speed of 60 kilometers per hour, it will take 4 hours to reach Lizhuang. It only took three hours to get there. How many kilometers does this car actually travel per hour on average?
4. The average speed of a train before speed increase is 7 1km, and it takes 12 hours from Qinhuangdao to Handan. After speeding up, the average speed is 95 kilometers per hour. How many hours does it take from Qinhuangdao to Handan after speeding up?
The coach from Beijing to Qingdao passes through Tianjin and Jinan. It departs from Beijing at 6: 30 in the morning with an average speed of 85 kilometers per hour. When does it arrive in Qingdao?
137km； From Beijing to Tianjin; 360km from Tianjin to Jinan; Jinan to Qingdao is 393 kilometers.
6. It is 936 kilometers from A to B, 2 16 kilometers from A to B in three hours, and 3 1066 kilometers from A to B in four hours. Which bus will arrive first?
7. A car is driving between A and B, with a speed of 60 kilometers per hour when it goes there and 40 kilometers per hour when it comes back. Find the average speed of this car going back and forth.
8. A student went from home to school at a speed of 5 km/h, took a bus at a speed of 20km/h after leaving 1/3, so he arrived at school two hours earlier than the specified time. How far is his home from school?
9. An airplane can fly in the air for up to 4 hours, flying out at a speed of 600km/h and flying back at a speed of 550 km/h. Q: How many kilometers can this airplane fly at the farthest?
10, the two trains are running on parallel tracks respectively, in which the length of the express train is 100m and the length of the local train is 150m. When the two trains travel in opposite directions, the time for the express train to pass through a window of the local train is 5s, so:
(1) When two cars are driving in opposite directions, the time required for the local train to pass through a window of the express train.
(2) If two cars are driving in the same direction, and the local train speed is 8m/s, how long does it take for the express train to catch up with the local train from the back to leave the local train?
1 1. An engineering team builds 85 meters of roads every day. According to this calculation, how many meters will the four engineering teams build roads in seven days?
12. The five workshops of the electric fan factory produced 2250 electric fans in 30 days. How many electric fans does each workshop produce on average every day? (Check after solving)
13. Li Shifu processes 49 parts per hour, while Master Zhang processes 54 parts per hour. They each do 8 hours. How many roles did Li Shifu play less than Zhang?
14. The fruit shop sent 25 baskets of apples and pears, each with 6 kilograms of apples and 8 kilograms of pears. How many kilograms are apples and pears?
15. When I participated in planting trees in spring, 52 people were in the fifth grade, and each person planted 26 trees; In the fourth grade, 48 people each planted 25 trees. How many more trees were planted in the fifth grade than in the fourth grade?