Math final application questions for the first year of junior high school! I want answers!!

1.A pool has 84 tons of water, and there are two water pipes A and B, with pipe A discharging tons per hour and pipe B discharging tons per hour. If the first pipe is opened, and then the second pipe is opened after 2 hours and 24 minutes, how many hours after the opening of the first pipe can the water in the pool be discharged?

2.The correspondent sent the letter from A to B and then immediately returned to A, sharing 3 hours and 52 minutes, going at a speed of 30 kilometers and returning at a speed of 28 kilometers, to find the distance between A and B.

3.A walks 5 kilometers per hour, and 2 hours after departure, B rides to chase A.

1) If B's speed is 20 km/h, how long does it take for B to catch up with A?

2) If B is asked to catch up with A when B has walked 14 km, ask B what is his speed?

1.Thinking about her mother, she went to the market to buy fruits, she first spent yuan to buy apples, and was ready to buy 3kg of oranges, the unit price of oranges is twice that of apples. How much should I pay to buy oranges?

2.Xiaohua borrowed a 120-page storybook, and she read 36 pages in 3 days. If you can only borrow for 8 days, how many pages should I read at least every day from day 4?

3.The canteen bought 360 kilograms of rice and plans to eat 30 kilograms a day. I actually ate 3 more days than planned, how many kilograms of rice did I actually eat every day?

4.A 340-kilometre-long stretch of road was built, with an average of 20 kilometres per day for the first two days. The rest of the part needs to be repaired in 4 days, how many kilometers per day is the average repair?

5.Two cars, A and B, drove opposite each other at the same time from two places 396 kilometers apart. Car A travels kilometers per hour, and vehicle B travels kilometers per hour. After a few hours of car encounters?

6.A certain transport team has to transport 10,000 bricks, and if the blocks are transported every hour, they can all be transported on time. If you want to ship it all 4 hours in advance, how many tens of thousands of pieces should be transported per hour.

7.A workshop can produce 120 parts of A every day, or 100 parts of B, or 200 parts of C, and 3, 2 and 1 of A, B and C parts can be matched into a set. Now it is required to produce the most complete sets of products within 30 days, how many days should each be arranged for the production of A, B and C parts?

8.A math reader and a Chinese reader. How much do two books cost?

9.A watermelon weighs kilograms, and a cantaloupe weighs kilograms. How many kilograms does a watermelon weigh more than a cantaloupe?

2. Decimal one-step multiplication and division application problem 1: How much yuan should be paid for a kilogram of wool yarn if you buy 3 kilograms? What about buying kilograms?

2. A professional group of silkworms raised 21 spring silkworms, with a total of 1240 kg of cocoons. How many kilograms of cocoons do you produce on average?

3. Two-step calculation application problem with three known conditions 1, Xiaohong read a storybook, read it for 5 days, read 12 pages a day, and did not read 38 pages. How many pages are in this book? (Draw a line diagram).

2. 3 bags of flour and 3 bags of rice were brought from the canteen. Flour bags weigh 25 kg and rice bags weigh 50 kg. How many kilograms of flour and rice were brought in?

3. The militia used 250 bullets for the first time, 320 bullets for the second time, 180 rounds less than the sum of the previous two for the third time, and how many bullets were used for the third time?

A vegetable company acquires 140 tons of a certain vegetable, ready to participate in the market sales of 6 tons of finishing per day, rough processing of 16 tons is planned to be completed in 15 days, the company is finishing for a few days, rough processing for a few days.

There are 28 members in Engineering Team A and 35 members in Engineering Team B, and a number of people from Team A will be transferred to Team B, so that Team B will be twice as large as Team A. How many people should be transferred from Team A to Team B?

A book city carries out student bai preferential book sales activities, where the one-time purchase of books does not exceed 200 yuan, a dao law nine-fold discount, of which 200 yuan is converted according to the edition of nine, and the part of the right to exceed 200 yuan is converted by eight. A student paid 72 yuan for the first time to buy a book, and the second time he bought a book to enjoy a 20% discount, he checked the price of the book he bought, and found that he saved a total of 34 yuan twice. then the student actually paid ( ) yuan for the second purchase of the book.

72 yuan) 80-72 = 8 (yuan).

34-8=26 (yuan).

200* yuan).

200-180 = 20 (yuan).

26-20 = 6 (yuan).

6 yuan) 200 + 30 = 230 (yuan).

A: The actual payment for the second time is 230 yuan.

Children, very talented, and know how to ask shamelessly, my brother is a postdoctoral fellow, I'll teach you to do: the first question, 1) 8a-5b-(3a-b) 2

2) Substitute a= into the final get, the second question I don't see is all baskets, the third question, 1) x+2x-40 + (2x-40) 2+30 to get 4x-30

2) Substituting x=50 into this equation results in 170

My brother gave you all the hand-shots, don't look at it, give me a satisfactory answer, thank you.

1. Solution: Let the speed of A be a meter second, the speed of B be b meter second, 13 minutes 20 seconds = 800 seconds, 1 minute 20 seconds = 80 seconds.

If a>b, then the two people are in the same direction, and every 800 seconds the two meet each other to get (a-b)*800=800;

The two people are in opposite directions, and every 80 seconds when the two meet each other to get (a+b)*80=800 to solve this equation, a = meter seconds; b = m seconds If a2, solution: let the triangle abc minimum angle number be a, according to the title, the slightly larger degree b is 3 2a, the maximum angle c degree is: a + 3 2a + 30, then:

According to the sum of the inner angles of the triangle equal to 180 degrees.

a+3 2a+(a+3 2a+30)=180°Solving this equation gives a=30° b=45° c=105°

1.Let the velocity of A be x minutes and seconds, and the speed of B be y minutes and seconds, 131 3y+800=131 3x 11 3x+11 3y=800 x=330, y=270

2.Let the second inner angle be x°, then 3 2x+x+3 2x+x+30=180 x=30°, and you can calculate the other two angles yourself.

2. The first inner angle is 30°

The second internal angle is 45°

The third inner angle is 105°

1. Solution: Let the speed of A be x and the speed of B be y, 13 minutes and 20 seconds = 800 seconds, and 1 minute and 20 seconds = 80 seconds.

If x>y, then (x-y)*800=800;(x+y)*80=800 solves this equation to obtain x= meters and seconds; y= meter seconds, if x3x 2=45 degrees.

45 + 30 + 30 = 105 degrees.

(1) Assuming that you apply for a loan of X million yuan for type A and a loan of y yuan for type B, you can get x+y=68

The solution yields x=12 y=56

2) (1) It can be obtained according to the title.

The solution is a=60

2) (2) Assuming that the electricity consumption x degree in June is obtained, [60 * solution x = 90

So 60*RMB).

Answer: In June, the total electricity consumption is 90 yuan, and the electricity fee should be paid.

3) Assuming that there are x excavators, then there are (21-x) loading and unloading trucks to get 750x=300 (21-x).

If x=6 is solved, then 21-6=15 (vehicles).

A: There are 6 excavators and 15 loading and unloading trucks.

You have time to type, read the book properly, and think about it seriously. It's all basic, and it's almost the same if you can't pass junior high school. Just provide the answers. 24，，90，，15。

One. Set up a type of loan of x million yuan, and a type of B loan of y yuan. According to the question, x+y=68, and 6%x+.

Two. （1.）

（1）x+y=68

The solution yields x=12 y=56

2) (1) It can be obtained according to the title.

The solution is a=60

2) (2) Assuming that the electricity consumption x degree in June is obtained, [60 * solution x = 90

So 60*RMB).

Answer: In June, the total electricity consumption is 90 yuan, and the electricity fee should be paid.

3) Assuming that there are x excavators, then there are (21-x) loading and unloading trucks to get 750x=300 (21-x).

If x=6 is solved, then 21-6=15 (vehicles).

A: There are 6 excavators and 15 loading and unloading trucks.

1. Green Valley Shopping Mall"Household appliances go to the countryside"The purchase price and selling price of designated models of refrigerators and color TVs are shown in the following table:

Category: Refrigerator, Color TV.

Purchase price (yuan) 2 320 1 900

The selling price (yuan) is 2 420 1 980

1) According to the national policy, farmers buy"Household appliances go to the countryside"Products can enjoy a subsidy of 13% of the selling price**. Uncle Tian, a farmer, went to the mall to buy it.

A refrigerator and a color TV, how much can I enjoy?

2) In order to meet the needs of farmers, the mall decided to purchase a total of 40 refrigerators and color TVs with no more than 85 000 yuan, and the number of refrigerators should not be less than the number of color TVs

Please help the mall to design the corresponding purchase plan;

Which purchase plan mall gets the most profit (profit = selling price purchase price), and what is the maximum profit?

Solution: (1) (2420+1980) 13%=572

A: You can enjoy a subsidy of 572 yuan.

2) Set up refrigerators to purchase x units, then color TV purchases (40-x) units, according to the theme, get.

2320x+1 900(40-x)≤85000，x≥ (40-x).

Solve the group of inequalities to get x

x is a positive integer

x= 19,20，21．

There are 3 purchase plans in the mall:

Plan 1: Buy 19 refrigerators and 21 color TVs.

Plan 2: Buy 20 refrigerators and 20 color TVs;

Plan 3: Buy 21 refrigerators and 19 color TVs.

Set up a shopping mall to get a total profit of y yuan, according to the theme, get.

y=(2 420 - 2 320)x+(1 980 -1 900)(40-x)=20x+3 200

20>0, y increases with x.

When x = 21, y max = 20 21 + 3 200 = 3 620

Answer: The shopping mall in option 3 has the largest profit, and the maximum profit is 3 620 yuan.

Answer: 1) m*(

3) The title is wrong, should be a steel mill in 2002 the annual output of 28,500t, 2003 is 31,350t, Q: What is the annual growth rate of the steel plant's output? then it is empty.

You're a pig, go home

1.A, two cars have been moving in opposite directions, A has traveled 60 kilometers per hour, the body is 150 meters long, has traveled 75 kilometers per hour, the body is 120 meters long, how long does it take for the two cars to meet each other from the beginning to the rear of the car?

2.A 100-kilometer hike, some people walk, the other part takes a car, both groups of people set off at the same time, after the car drives to the destination, and then turn back to pick up the part of the people walking, if the speed of the walker is 5 kilometers, 1 hour ahead of the car, when the speed of the car is 60 kilometers, ask the walker how long after the departure and the car that picks him up?

3.A and B drive from place A in the same direction, A sets off first, half an hour later has been chasing A at a speed of 80 kilometers per hour, if it has been an hour after catching up with A, ask for the speed of car AA, two cars have been moving in opposite directions, A has traveled 60 kilometers per hour, the body is 150 meters long, has traveled 75 kilometers per hour, the body is 120 meters long, how long does it take for the two cars to meet each other from the beginning to the rear of the car?

150+120) 1000 (60+75) = Hours = Seconds.

2.A 100-kilometer hike, some people walk, the other part takes a car, both groups of people set off at the same time, after the car drives to the destination, and then turn back to pick up the part of the people walking, if the speed of the walker is 5 kilometers, 1 hour ahead of the car, when the speed of the car is 60 kilometers, ask the walker how long after the departure and the car that picks him up?

Set the walker to set off and meet the car that turned back to pick him up after a while:

100×2=[60×(a-1)+5×a

a = 4 hours.

3.A and B drive from place A in the same direction, A sets off first, half an hour later has been chasing A at a speed of 80 kilometers per hour, if it has been an hour after catching up with A, ask for the speed of car A

Set the speed of the armored car to be x kilometers.

80 x = 70 kmh.