1, Mingming bought a calculator in the store, and got a 15% discount, which cost 68 yuan. What is the original price of this calculator? Xiaohua's family harvested 4000 kilograms of rice the year before last. Last year, due to pests, the output decreased by 35% compared with the previous year. How many Jin of rice did Xiaohua's family collect last year?

3. The current price of a commodity is 18 yuan, with a loss of 25%. How much is the loss? If you want to make a profit of 25%, how much should you sell it?

4.30 kg of salt water with a salt content of 10%. How many kilograms of salt can be added to make salt water with a salt content of 25%?

5. The original price of a leather coat is 1800 yuan, but now it has been reduced. What's the discount on products sold in 270 yuan?

6. The insurance company has 120 employees, of which male employees account for 50% of female employees. How many male employees are there in this insurance company?

7. An engineering team built 600 meters on the first day, 20% of the total length on the second day and 25% on the third day. At this time, 75% of the total length was repaired. What is the total length of this highway?

8. Xiaojun bought a set of discounted clothes at the price of 72 yuan, which was cheaper than the original price by 8 yuan. How much is the discount on this suit?

9.1520kg salt water has a salt content of 25%. How many kilograms of water need to be evaporated to turn these brine into brine with a salt content of 50%?

10. A circular fish pond with a circumference of 314m. What is the area of this fish pond?

1 1. A round vegetable field with a diameter of 20 meters. Now, how many square meters of plastic film are needed to cover vegetable fields? If the film price per square meter is 0.5 yuan, how much do these films cost?

12. The outer diameter of the bicycle wheel is 70cm. If the wheels rotate 100 cycles per minute on average, it takes about 25 minutes to get from Wangzhigang Town to Baoying County. How many kilometers is it from Wangzhigang Town to Baoying County?

13. Build a canal with a length of 1800 meters. After five days' work, the repaired canal accounts for13 of the unrepaired canal. According to this schedule, how many days will it take for the canal to be completed?

14, sixth grade math interest group activities, students didn't participate in 3/7, and then 30 people participated, so students didn't participate in 2/3, how many students were in sixth grade?

15,' 5/6 of the school's art group is just 5/8 of the science and technology group. It is known that there are 24 people in the art troupe. How many people are there in the science and technology team of this school?

Mathematics application problems in the second volume of grade two and six

1, Xiaoli's mother bought a set of 500 yuan sportswear for Xiaoli, and now the store has a 15% discount. How much cheaper can it be now? 2. When department stores engage in promotional activities, brand A shoes will be reduced by 100 yuan when they reach 200 yuan, and brand B shoes will be "discounted", that is, 60% discount will be given first, and then 5% discount will be given on this basis. If both brands have a pair of shoes priced in 360 yuan, how much is the difference between them?

3. A pile of conical sand piles, with a bottom circumference of 62.8m and a height of 3m. Spread this pile of sand on a road with a width of 10 m and a thickness of 5 cm. How long is this road?

4. The front wheel radius of the roller is 5 decimeters, the wheel width is 2 meters, and it rotates 30 times per minute. How many square meters is the road surface area of this roller for half an hour?

In a bottle with a diameter of 10cm, the height of water is 8cm. Turn the bottle cap upside down, tighten it and lay it flat. The waterless part is cylindrical with a height of 17cm. What is the volume of this bottle?

6. A section of sidewalk, paved with square bricks of 25 square decimeters, needs 960 yuan. How many square bricks does it take to pave the ground with an area of 16 square decimeter? (Answer with proportional knowledge)

7. A coat is more expensive than a pair of trousers 160 yuan, in which the price of trousers is 3/5 of that of a coat. How much is a pair of trousers?

8. There are 60 black rabbits in the feeding group, and there are more white rabbits than black rabbits 1/5. How many white rabbits are there?

9. The school wants to dig an 80-meter-long sewer. 1/4 was dug on the first day, and 1/2 was dug on the second day. * * How many meters have you dug in two days? How many meters are left?

10, Xiao Ming reads story books. On the first day, he read 1/9 of the whole book, and the next day, he read 24 pages. The ratio of pages read in two days to remaining pages is 1: 4. How many pages are there in this book?