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A store sells two goods at the same time, and the price is 600 yuan. One is genuine goods, and it can earn 20%; the other is processed goods, and it has to pay 20%. In terms of these two goods, is it a profit or a loss?
Genuine products: 600 △ 1.2 × 0.2, = 500 × 0.2, = 100 (yuan); processed products: 600 △ 1-20% × 20% = 600 △ 0.8 × 0.2, = 750 × 0.2, = 150 (yuan); total: 150-100 = 50 (yuan), that is, compensation. A: compensation
Several math problems (sixth grade, speed)
1. Class 6 (1) donated 360 books to the "Hope Project", which is 3 / 4 of the books donated by class 6 (2). The average value of each book is 21 / 4 yuan. How many yuan did class 6 (2) donate?
2. A barrel of oil, pour out part of it and leave 5 / 8. The remaining five days will be used up, with an average of 3 / 4 kg per day. How many kg of this barrel of oil used to be?
3. In Nantong port, there are four brothers who want to buy a boat together. The eldest brother pays 1 / 3 of the other three, the second brother pays 1 / 5 of the other three, the third brother pays 1 / 2 of the other three, and the fourth brother pays 80000 yuan. How much is the boat worth?
(homework, due tomorrow, please speed up)
1.360 / (3 / 4) = 480, so the value is 480 * 21 / 4 = 2520 yuan, 2.5 × 3 / 4 = 15 / 4kg. 3. Let the eldest brother give x 10000 yuan, the second is y 10000 yuan, the third is Z 10000 yuan, x = 1 / 3 * (y + Z + 8) y = 1 / 5 * (x + Z + 8) z = 1 / 2 * (x + y + 8) the solution is x = 8, y = 16 / 3, z = 32 / 3, the price of the ship is x + y + Z + 8 = 320000, choose me!: -
A helicopter starts from a position with an altitude of 450m, rises for 60s at a speed of 20m / s, and then decreases for 120s at a speed of 12m / s. what is the height of the helicopter?
The height of the helicopter is 450 + 20 * 60-120 * 12 = 450 + 1200-1440 = 210m
The fuel carried by an aircraft can fly for up to 6 hours. For flight training, when going downwind, it can fly 1500 kilometers per hour; when returning upwind, it can fly 1200 meters per hour. How long does the aircraft have to fly back at most?
If the speed ratio is 1500:1200 = 5:4, then the time ratio is 4:5, 6 × 45 + 4 = 6 × 49 = 83 (hours). A: if the aircraft flies for 83 hours at most, it has to fly back
RELATED INFORMATIONS
- 1. A person needs 120000 yuan to buy a commercial house with an area of 100 square meters. He has paid 30000 yuan in the down payment. The rest of the money he needs is a mortgage loan from the bank. The loan lasts for 10 years and the annual interest rate is 2.5% (not considering compound interest). How much is the actual value per square meter of his house? (loan interest = loan amount × annual interest rate × time)
- 2. Around a round pool with a diameter of 10 meters, build a stone road with a width of 1 meter. What is the area of this stone road?
- 3. Party A and Party B rode bicycles from AB to ab. Party A started 15 minutes earlier than Party B. the speed of Party A and Party B was 3:2. When they met, Party A walked 6 kilometers less than Party B. they walked for 1 hour and 30 minutes to find the speed of Party A and Party B and the distance between the two places
- 4. A and B bicycled from two places 66 kilometers apart. It is known that a travels 3 km more per hour than B. after meeting each other for 2 hours, the speed of a and B is calculated Solve by equation
- 5. Party A and Party B set out at the same time from AB, which is 120 kilometers away, and they were walking towards each other. Party A rode 18 kilometers per hour, and Party B walked for five hours before they met, Solve by equation
- 6. The walking speed ratio of a and B is 13:11. They start from a and B at the same time and walk in opposite directions. They meet half an hour later. It's like walking in opposite directions. How small does it take for a to catch up with B
- 7. The speed ratio of a and B is 2:3. When they meet, a walks 6 km less than B. It is known that B walks for 1 hour and 30 minutes. The speed of a and B and the distance between two places are calculated
- 8. A and B are facing each other. A leaves 15 minutes earlier than B. the speed ratio of the two cars is 2; 3. When they meet, a walks 6 kilometers less than B. It is known that B walks for 1 hour and 30 minutes It is known that Party B walked for 1 hour and 30 minutes to find out the speed of the two cars and the distance between them
- 9. On a map with a scale of 1:1000000, the distance between a and B is 10 cm, while the distance between a and B on another map is 5 cm What is the scale of the other map? What rules do you find by comparing the data?
- 10. On the map with a scale of 1; 5000000, the distance between a and B is 5.4cm When does it start from place a at 8 a.m. and arrive at place B/
- 11. The distance between a and B is 930 km, and they are running in opposite directions. A is 80 km / h, B is 90 km / h, and B's car is delayed for one hour How long does it take from departure to meeting?
- 12. From station a to station B, it takes 7 hours for car a and 7 hours and 30 minutes for car B. car a is 4 kilometers faster than car B. find the distance between station a and station B and the speed of car a and station B
- 13. The distance between a and B is 460 kilometers. A and B start from a and B at the same time. They travel 60 kilometers per hour and meet each other for more than 48 hours The distance between a and B is 460 km, and a and B vehicles leave from a respectively. B starts at the same time. One car travels 60 kilometers per hour, and two cars travel 48 kilometers per hour. They meet each other in a few hours
- 14. AB is 1000 meters apart. Party A and Party B start from two places at the same time and walk back and forth. The first meeting is 100 meters away from the midpoint of AB, where is the second meeting?
- 15. The distance between the two places is 1800 meters. Party A and Party B set out at the same time. Party A is fast and Party B is slow. They meet in place a in 12 minutes If each person walks 25 meters more, then the meeting place B is 33 meters away from the ground A. how many meters does a walk at the original speed per minute?
- 16. 1. A and B vehicles leave from two places 420 kilometers apart at the same time, and meet four hours later. The speed ratio of a and B vehicles is 4:3. What are the speeds of a and B vehicles? 2. There are three groups in class 6 (1) to plant trees. Each group plants trees according to the number of people. How many trees should each group plant? There are 16 people in the first group, 14 people in the second group and 18 people in the third group. There are 72 trees in total
- 17. The distance between a and B is 352 kilometers. A and B cars drive from a and B. a car travels 36 kilometers per hour, and B car travels 44 kilometers per hour. B car starts 32 kilometers after a car leaves due to accident. Which car takes more distance from each other to meet? How many kilometers more?
- 18. From a to B, the express train takes 6 hours and the slow train takes 10 hours. Now the two trains leave from a and B at the same time. When they meet, the express train takes 240 km, How many kilometers is the distance between the two places?
- 19. Example 3: the fast train and the local train leave from a and B at the same time. It is known that the fast train travels 60 kilometers per hour and the local train 52 kilometers per hour. After a few hours, the fast train meets the local train at the midpoint of 32 kilometers. What is the distance between a and B?
- 20. Fast train and local train are expelled from a and B at the same time. The fast train runs 80 kilometers per hour, while the local train runs 60 kilometers per hour. After three hours, the fast train runs 40% of the whole journey How many kilometers are the two cars at this time? Formula!