Grade 4 Unit 4 decimal application problems

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1 To make a rectangular bathtub (without a lid), 8 decimeters long, 4 decimeters wide, and 6 decimeters high, how many square decimeters of glass do you need at least? If you pay 4 yuan per square decimeter of glass, how much money do you need to buy glass at least?

2 A room is 6 meters long, 3 meters wide, and 3 meters high, with doors and windows of 8 square meters. Now to cement the four walls and the top of this room, how many square meters of area should the cement be painted? If you need 4 kg of cement per square meter, how many kg of cement do you need?

3 How many kilograms does a cube of stone weigh about kilograms per cubic meter of stone with an edge length of 5 decimeters?

4 A box of biscuits is 20 cm long, 15 cm wide and 30 cm high, and now it is necessary to put label paper around it, what is the square centimeter area of this label paper?

5 How many bricks does the school need to buy if it needs 525 bricks per cubic meter to build a wall 20 meters long, wide and 2 meters high?

6 A cuboid tank contains 60 liters of potions, and it is known that the tank is 5 decimeters long and 3 decimeters wide, how many decimeters is it deep?

7 How many centimeters is the length of a cube of iron that is 80 centimeters long, and now it is to be cast into a cuboid with a cross-sectional area of 20 square centimeters?

8. The area of a surface is a cube of 36 square meters, and what is the sum of all its edges?

9. If a rectangular frame with a length of 10 cm and a width of 7 cm is welded with this wire, how many cm should it be high?

10. Every day swimming pool, 25 meters long, 10 meters wide, deep meters, tile laying around the pool and at the bottom of the pool, if the side length of the tile is 1 decimeter square, then at least how many tiles are needed?

11. How many pieces can be cut into a cube with an edge length of 12 cm into a small cube with an edge length of 3 cm?

12. A kind of rectangular cardboard box, 10 cm long, 6 cm wide, 5 cm high, with 2 square meters of cardboard 210 sheets, how many such cardboard boxes can be made? (excluding interfaces).

13. The sum of the edges of a cuboid is 72 centimeters, its length is 9 centimeters, its width is 6 centimeters, and its surface area is how many square centimeters?

14 How many cubic decimeters does a brick have in length 24 centimeters, decimeters in width, and 6 centimeters in thickness?

15 How many liters of water can be filled in a cube-shaped glass fish tank, measured from the inside to meters long?

16 A rectangular bunker filled with sand was 3 meters long, 2 meters wide and 2 meters deep, and weighed 1,400 kilograms per cubic meter of sand. How many tons of sand are in this bunker?

17 If there is a square piece of timber with a cross-section of 2 centimeters, how much does this square timber occupy when it is placed? What is the volume?

What do you call this question, how do you calculate it? Is it difficult for us to help you turn over the book, who has the book?

A bottle of apple juice yuan, a bottle of pomegranate juice yuan, how many yuan in total?

Xiaohong is meters tall, taller than Xiaogang, Xiaoli is taller than Xiaogang, how tall is Xiaoli?

The surface area of the earth is 100 million square kilometers, the land area is 100 million square kilometers in the middle period, and the ocean area is hundreds of millions of square kilometers more than the land area?

Xiaohong's piggy bank originally had yuan, she bought a yuan pen yesterday, and today her mother gave her yuan, how much money is in the piggy bank now?

A pair of sneakers, a skipping rope, is 50 yuan enough for dad to pay? How much money should I get back?

There are grams of vitamins in every 10 kg of orange juice, so how many grams of vitamins are in 100 kg?

Football dollars, basketball dollars, how much in total?

1.Xiaohong's height is 156 centimeters, Xiaofang's height is meters, and Xiaohong is much taller than Xiaofang.

2. Suguo supermarket shipped tons of cantaloupe, watermelons more tons than cantaloupe, how many tons of two kinds of melons were transported.

3. The students of Zhangzhuang Primary School spent more yuan on repairing tables and chairs, which was more than binding books. How much did it cost to bind the book.

4, A and B are 220 meters apart, Xiaohua and Xiaohong are from A and B respectively, when Xiaohua walked the meter, Xiaohong walked the meter, how many meters are the two meters apart.

5. The school uses 200 yuan to buy books, 87 yuan and 5 jiao to buy science and technology books, and 32 yuan and 4 cents to buy story books.

6. A long bamboo pole of one meter is inserted vertically into the pool, the mud part of the bamboo pole is meters, the part that exposes the water surface is meters, and the depth of the pool water is how many meters.

7. A bottle of oil weighs kilograms with a bottle, and after half of it is used, the bottle still weighs kilograms. It turns out how many kilograms of oil there is and how many kilograms the bottle weighs.

8. Build a road, it has been repaired for kilometers, and the rest is less than the repaired kilometers, how many kilometers is the total length of this road.

the algorithm of the decimal point; Addition and subtraction to figure out how many decimal places to align, then add and subtract, multiply to the right side, and then multiply each bit, and then do sum, and finally count the number multiplied by how many decimal places, from the right number of how many decimal places you can put on the decimal point.

1.Xiao Ming is meters tall, Xiao Hua's height is shorter than Xiao Ming's, and Xiao Hua's height is 2Xiaohong took the yuan to buy vegetables, bought the yuan of vegetables, and asked how much money was left3A bottle of soda yuan, plus the sugar of yuan, how much is in total.

4.The road repair team repaired a kilometer of road on the first day and a kilometer on the second day, and asked how many meters were repaired in the two days.

1.In the long jump competition, Xiaowei jumped rice, Xiaotian jumped more meters than Xiaowei, Xiaopeng jumped less meters than Xiaotian, how many meters did Xiaopeng jump?

2.Mr. Zhang bought two reference books, "Mathematics Guidance", which is more diverse than "Mathematics Problem Bank", how much yuan does Mr. Zhang have to deal with?

3 On a certain day, the temperature in the morning is Celsius, the temperature is higher at noon, and the temperature is lower at night than at noon, what is the temperature at night?

4 Xiao Ming has yuan, Xiao Hua has yuan, the two want to buy a football together, the ** of the football is twice the sum of the money of the two of them, how many yuan are they missing?

Great Khan. 1 ton = 1000 kg 1 kg = 1000 g 1 km = 1000 m.

1 m = 100 cm 1 cm = 10 mm.

A car and a motorcycle depart from two places 184 kilometers apart at the same time, drive out opposite each other, and after an hour of meeting, the motorcycle travels 70 kilometers per hour, how many kilometers does the car travel per hour?

Motorcycles go out of kilometers after hours)

The car travels 184-112 = 72 (km) in hours

The speed of the car is 72 km/h).

380-50 = 330 (km).

330 (50+60)=3 (hours).

A: After three hours of encounter.

Car A drove for 1 hour and walked 50 kilometers, and then both cars A and B drove and walked in the opposite direction, so after 330 (50+60) = 3 hours, the two cars met, and it would be.

（380-50）/（50+60）=3。That is, the two cars met after 3 hours.

After A walks for an hour, the distance between A and B changes from 380 to 330, because they are walking in the opposite direction, so the question is equivalent to how long it takes a person to complete a 330km journey at a speed of 110km per hour, the answer is 3h, that is, three hours after B's departure, the two cars meet! Complete!

At 10:00, car A ran 50 kilometers. The remaining 330 kilometers, divided by the sum of the speeds of the two cars 110, equals 3. So car B and car A meet 3 hours after departure.

After the departure of car B, the two cars meet after x hours.

Car A walked away (x+1) hours when they met.

x+1)*50+60x=380

Solution: x=3Answer: After 3 hours after the departure of car B, the two cars meet.