81 6 A project team dug a 4.2km canal in 24 days, 1 / 5 more than the actual number of days. How many kilometers were actually dug every day?

4.2 [(24 / (1 + 1 / 5)] = 0.21 km

RELATED INFORMATIONS

1. 81 3 Passenger cars and freight cars start from both places at the same time and travel in opposite directions. The passenger cars travel 35 kilometers per hour, which is 5 / 7 of the speed of freight cars. After 3.5 hours, the two cars meet. How many meters is the distance between the two places?
2. Xiao Ming's mother went shopping in the supermarket. It is known that 13 eggs, 5 duck eggs and 9 quail eggs cost 9.25 yuan; 2 eggs, 4 duck eggs and 3 quail eggs cost 3.20 yuan. Q: how much does Xiao Ming's mother want to pay for one egg, one duck egg and one quail egg?
3. Recruits training, soldiers Xiaoxi 10 shot hit 81 ring, so Xiaoxi at least one shot hit 9 ring, why?
4. Recruits training, soldier Xiao Li 5 shot hit 41 ring, soldier Xiao Li at least one shot hit 8 ring. Why?
5. Recruits training, soldier Li 9 shot hit 82, he has at least one shot hit several rings
6. 81 5——6 Xiaoqiang, you have already made 7 / 10 of the whole journey from tunnel a to place B. if each branch is 90 meters, you can reach place B in 6.5 minutes. How many meters are there between a and B? A project team dug a 4.2km canal in 24 days, 1 / 5 more than the actual number of days. How many kilometers were actually dug every day?
7. 【1】 The tire diameter of a car is 8dm, and it runs 45.216km at 1 hour. How many turns does the car wheel turn per minute? 【2】 Lili read a book, read 24 pages on the first day, read 25% of the whole book on the second day, and read 40% of the whole book in two days. How many pages are there in this book? 【3】 There is a round iron ring with a diameter of 20cm. Now we need to fold it into a rectangle, so that the ratio of length to width is 3:1. What is the length and width of the rectangle? 【4】 The ratio of a, B and C is 1:2:3. The average number of a, B and C is 120. What are the numbers of a, B and C?
8. Xinxin garment factory has to produce a batch of school uniforms. The ratio of completed sets to unfinished sets in the first week is 1:3. If 250 sets are produced again, half of this batch of school uniforms will be finished. How many sets are there in total?
9. Urgent! Sixth grade math problem! Online, etc Math problem: Mr. Li bought a house with a unit price of 9400 yuan per square meter and an area of 101 square meters. He paid 2 / 5 of the total down payment and borrowed 300000 yuan from the bank's provident fund. The rest of the money was mortgaged by the bank. How many yuan does Mr. Li need to borrow? Detailed description, help you, have to say clearly, the answer is 269640, please step by step to explain the idea, good words plus points. Urgent! Online, etc
10. When 80% of the color TV sets are sold, the rest will be sold at a 20% discount. What's the actual profit of this batch of color TV sets? 2. After 75% of the total number of peaches sold in a supermarket during the May Day holiday, another 120 kg of peaches were transported. At this time, the total number of peaches increased by 5% compared with the original? 3. Xinglong shopping mall adopts the method of "get 50 free of 300" to promote sales. It is stipulated that if the purchase is over 300 yuan, 50 yuan gift certificate will be given, and the part less than 300 yuan will be omitted. The gift certificate can replace cash in the next shopping, but the part using the gift certificate can not enjoy the discount of "get 50 free of 300 yuan" A customer first bought a product with 1000 yuan, and then bought B product with these gift certificates and 280 yuan in cash. Q: how much discount does this customer enjoy when buying a and B products?
11. My father is 28 years older than Xiao Liang. Seven years later, my father's age is just three times that of Xiao Liang. How old are my father and Xiao Liang after seven years?
12. My father is 33 years old and my son is 5 years old. A few years later, my father is three times as old as my son
13. My father is 27 years old. Four years later, my father is four times as old as my son. How old is my father now?
14. 77*13+255*999+510 =77*11+77*2+255*999+255*2 =77*11+154+255*1001 =77*11+154+255*(1000+1) =77*11+154+255*1000+255*1 =847+154+255000+255 =1256+255000=256256 Sorry, I can't understand this process, please explain
15. 77×13+255×999+510．
16. 77*13+225*999+510
17. 77×13+255×999+510．
18. 77×13+255×999+510．
19. 0, 1, - 3, 7, - 15, 31. What is the 100th number
20. Find the rule 3, 7, 15, 31, 63___ ,255