Spiders have eight legs, dragonflies have six legs and two pairs of wings, and cicadas have six legs and 1 pairs of wings. Now these three kinds of bugs have 18, 1 18 legs and 20 pairs of wings. How many bugs are there in each species?

It is known that 50 people in the class have done five questions, of which the first question is wrong by four, the second by six, the third by nine, the fourth by two1and the fifth by 38.

1, PLA soldiers reclaimed a parallelogram vegetable field. Its bottom is 24 meters and its height is 16 meters. What is the area of this land?

2. Trapezoidal wheat experimental field with an upper bottom of 86m, a lower bottom134m and a height of 60m. How many square meters is its area? How many hectares?

3. Triangular land with a bottom height of 358m and a height of 160m. What is the area of this land? How many hectares?

Second, summarize the application questions

1. The People's Liberation Army Transportation Company transports a batch of coal. If each truck is loaded with 4.5 tons, it will take 16 cars to transport it at one time. If each truck is loaded with 6 tons, how many cars will it take to transport it all at once?

2. Students put flowers, each with 9 pots, which requires 36 people; If 18 people want to put it, how many pots should each person put?

Third, the application of three-step calculation method

Taiyanggou Primary School held a math knowledge contest. There are 60 participants in the third grade and 45 participants in the fourth grade. The number of participants in the fifth grade is twice that in the fourth grade. How many people took part in the competition in the third grade?

Fourth, meet the application problems

1, Zhang Ming and Li Hong set out from two places at the same time, facing each other. Zhang Ming walks 50 meters per minute and Li Hong walks 40 meters per minute. 12 minutes later, they met. How many meters are they apart?

2. The distance between Party A and Party B is 255km, and two cars leave both places at the same time. Car A travels 48 kilometers per hour and car B travels 37 kilometers per hour. Two cars meet in a few hours.

5. List simple equations to solve practical problems

Xiangqun Stationery Factory can produce 250 pencil boxes per hour. How many hours can you produce 10000?

2. The factory sent a batch of coal, burned 28 tons, and left 13 tons. How many tons is this batch of coal? (Answer in two ways)

Six, about the application of cuboids and cubes, the calculation of surface area and volume.

1, a rectangular iron box, length 18cm, width 15cm and height 12cm. How many square centimeters of iron does it take to make this iron box?

2. The side length of the cube is15cm. What is its surface area and volume?

1. Two trains leave from A and B at the same time, and meet at 48km after 4 hours. As we all know, the speed of the local train is five-sevenths that of the express train. What's the speed of the express train and the local train? How many kilometers is it between A and B?

2. With the cooperation of Party A and Party B, a batch of parts can be completed in 12 days ... After several days of cooperation, B asked for leave because of something, and B only completed three tenths of the total task. A went on doing it, and it took 14 days from the beginning to the completion of the task. Excuse me: How many days did A do it alone?

3. The construction of a section of highway was originally planned to be completed in 50 days for 120 people. After working for a month (calculated as 30 days), 20 people were transferred to repair other sections. How many days do the remaining staff need to work more than originally planned to complete the task?

1. What time does the train station clock strike? For example, 1 calls once, twice at 2 o'clock and once every half hour. How many times does this big clock strike every day and night?

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Two cars drive from a to b at the same time. The car travels more than the big car12km/h. The bus will arrive in B in 4.5 hours. It returns along the original road and meets the cart at 3 1.5 km at B. How many kilometers does the cart travel per hour? Amateur Boshu I K9DB t c

j ' y/N9DCF \ f ' pj03。 A pool can be filled with a single nozzle in 40 minutes, and it can be filled with a single nozzle 1 hour. If two pipes are opened at the same time, how long will it take to fill three quarters of the whole pool? Uncle Bo: {w "Z2S0D3Q &; R w'W8P5f

Boshu a6ZV z ` R, a fan.

4. Transport a batch of wheat with the same load, which is 5/6 of the total, 1 10 tons. How many tons are there in this batch of wheat?

Camping activities were held. At noon, the monitor went to the teacher in charge of logistics to get a bowl. The teacher asked, "How many people are there?" "One ***36." The monitor replied. Fans Boshu 4Y "k l5y" # E

The teacher said, "You can get it yourself, according to one person's rice bowl, two people's vegetable bowls and three people's soup bowls." This causes problems with the display. Can you help him?

6. There are 20 baskets of oranges, each weighing 27 kilograms. If each basket contains 1/9, how many kilograms is each basket? How many baskets can hold this basket of oranges?

7. A train can completely cross a 572-meter-long bridge in 64 seconds, while it only takes 20 seconds for the train to cross a tree on the roadside. How long is the train?

8. It takes 55 minutes for someone to travel from A to B at a speed of 12 km/h and from B to C, G and * * * at a speed of 9 km/h.. It takes 8km/yes to return from C to B, 4km/yes to return from B to A on Monday, and 1.5h to return to work. Find the distance between a and C.

On your own. Don't depend on others. I have no answers to these application questions. You won't do this again. Don't rely on others. believe in yourself