1. Put a sweet potato into a cubic container with a side length of 25 cm. The sweet potato was completely immersed in the water, and the water surface rose by 0.5 decimeter. What is the volume of sweet potato?

2. An iron block with a volume of 20,000 cubic centimeters sinks into a cuboid container with a length of 5 decimeters and a width of 2 decimeters. How many decimetres has the water surface risen?

3. Saw a cube into three identical cuboids, and the surface area increased by 64 square centimeters. What is the surface area and volume of the original cube?

4. A piece of wood is sawed into 7 sections, and the sawing time for one section is the total time ().

5. Add hundreds of semicolons after a number, and this number is (). If you remove the percent sign after the percentage, the number will be ().

6. The sum of the sides of a cuboid is 96 decimeters, the length is 9 decimeters and the width is 8 decimeters. What is its volume?

7. There is 50g of sugar in the container, and the sugar content is 10%. If10g sugar is added to the sugar water, what is the sugar content at this time?

8. A batch of chemical fertilizers was produced in May. Actually completed 1/3 of the planned quantity in the first half of the year, completed 40% of the planned quantity in the middle, and produced 52 tons in the second half of the year. How many tons of chemical fertilizer do you plan to produce?

9. The canteen should be a glass counter, 2.2 meters long, 40 centimeters wide and 80 centimeters high. Now it is necessary to install angle iron around the counter. How many meters of angle iron does this counter need? If glass is installed around and at the top of the counter, what area of glass is needed?

10, a tin plate is 25 cm long and 4/5 long. After removing the square with equal area at four corners, it is just made into an iron box without a cover, which is 5 cm deep. What is the volume of this iron box?

1 1. A cultural store sells 48 boxes of colored pens a day, 7/9 of which are in the afternoon. How many boxes of colored pens do you sell in the morning?

12. At present, 40 kilograms of sugar water contains 10%. After evaporating several kilograms of water, the sugar content of sugar water is 25%.

13.5/6 tons of wheat can be ground into refined flour 1 2 tons,1ton of wheat can be ground into refined flour. How many tons? How many tons of wheat does it take to grind 1 ton of refined flour? What about grinding 6 tons of refined powder?

14. Cut the 9/ 10 meter long iron wire into three equal parts, each part is () meters long and each part is () meters long.

15. Pour out a bottle of sugar water with a sugar content of 40% and fill it with water. The concentration of sugar water at this time is ().

16. forging a cubic billet with a side length of 0.6m into a rectangular steel with a cross-sectional area of 0.08m2, how long is the steel?

17. A packing box is 6 decimeters long and 4 decimeters wide, accounting for exactly 20% of the total length of the packing box. What is the height of this packing box?

18. An office is 6m, 5m wide and 3m high. After deducting the door and window area of 34 square meters, use 0.5 liter of paint per square meter, and paint 10.5 yuan. How much does it cost to paint this office?

19. Xiaoming's mother bought a 20% discount color TV set in the appliance supermarket and spent 2400 yuan. A few days later, the mall sold the color TV at 75% off the original price. How much did her mother spend?

20. Xiaoxiao's father is 32 years older than her. Xiaoxiao's age this year is just 1/5 of his father's age. How old are Xiaoxiao and Dad this year?

2 1. A batch of books are sold at 25% off the original price, which is cheaper than the original price ().

22. There are 800 apples and peaches, of which apples account for 2/5, and some apple trees are planted. Now, apple trees account for 17/25 of the two kinds of trees. How many apple trees have been planted?

23.750g of salt water containing 20% salt. After adding some water, the salt content is 8%. How many grams of water?

24. 25% of A is equal to 1/5 of B. If A is 80, B is (), if B is 80, A is ().

25. The survival rate of a batch of saplings is 98%. To ensure the survival of 196 saplings, it is necessary to plant () trees.

26. A 10% discount means that the price is ()% of the original price and ()% cheaper.

27. 12kg is less than 15kg ()%, and 15kg is greater than 12kg ()%.

28. Aunt Zhang sold two sets of skirts at the price of each set in 480 yuan. One set was 20% higher than the purchase price and the other was 20% lower than the purchase price. Is Aunt Zhang a profit or a loss?

29. When one side of a square is three times and the other side is four times, the circumference of a rectangle is 96 cm. What is the circumference of the original square?

30. It is known that when water freezes, its volume increases111. If the volume of water is 22 cubic decimeters, what is the volume of ice? If the volume of ice is 36 cubic decimeters, what is the volume of water?