At the same time, open a, b, c, 12 minutes to fill the pool.
At the same time, open b, c, d, 15 minutes to fill the pool.
Turn on A and D at the same time, and the pool will be filled in 20 minutes.
How many minutes can A, B, C and D drive at the same time to fill the pool?
Answer; 10 point
2. Someone plans to process parts in 15 days. If five parts are processed every day, they can be finished three days in advance. How many parts are there in this batch?
Answer; 300
3. Only Team A and Team B need 65,438+00 days, and Team C needs 7.5 days to complete. In the cooperation of three teams, it takes 1 day for team A to go out, and it takes half a day for team C to complete it. How many days does it actually take for three teams to work together?
Answer; 3.5 days
One day, Xiaoming's watch fell to the ground. He didn't break it at a glance, and he didn't care. As before, he set his watch at half past eight in the evening. The school stipulated that he should arrive at school at 7: 30, but he arrived at school at 7: 30 the next morning, but it was 10 minutes late. The teacher didn't blame him, asked about the situation and smiled, saying that the watch might not be accurate. But be careful, this is the way.
Answer: 10/ 1 1
1. A factory has 360 kilograms of raw materials A and 290 kilograms of raw materials B. It is planned to produce 50 products A and B with these two raw materials. It is known that it takes 9 kilograms of raw materials A and 3 kilograms of raw materials B to produce one product A, which can benefit 700 yuan. To produce a type B product, 4 kg of type A raw materials and 10 kg of type B raw materials are needed, and the profit can be 1.200 yuan.
1) Let the total profit from the production of products A and B be Y (yuan), and X products A will be produced. Try to write the relationship between y and X.
2) Arrange the number of production pieces of products A and B as required. What kinds of production schemes are there? Please design it.
3) Using the nature of the relationship listed in (1), which production scheme has the largest total profit? What is the maximum profit?
Suppose that X pieces of product A are produced and 50-x pieces of product B are produced.
According to the meaning of the problem, the inequality group is obtained:
9x+4(50-x) 360
3x+ 10(50-x) 290 equals 30.
According to the meaning of the question, x can only be 30,365,438+0,32, and the corresponding value of (50-x) is 20,654,38+09,654,38+08, so there are three generating schemes:
The first production plan: produce 30 products A and 20 products B;
The second production scheme: produce 3 1 piece of a product and 0/9/piece of b product;
The third production scheme: produce 32 pieces of A products, 18 pieces of B products.
The functional relationship is: y = 700x+1200 (50-x) = 60000-500x, where x can only be 30,3132.
Because the value of linear function y decreases with the increase of x, when x=30, the total profit is the largest, and the maximum profit is y=60000-500X30=45000 (yuan).
At a sports meeting in our school, the teacher distributed a bunch of badminton to each competition group. If there are three in each group, there are eight left. If each group has 5 shuttlecocks, the last group will get less than 3 shuttlecocks; How many competition groups are there?
Answer: 6 groups
A garment factory has 70M A fabric and 5 1M B fabric, and now plans to produce 80 sets of M and N fashions with these two fabrics. It is known that a fabric 1 is needed to make a set of M-fashion. 1M, where 0 is b fabric. 4M, 50 yuan can make a profit; Making N-fashion requires a fabric. 6M, 0 is B fabric. 9M, 45 yuan can make a profit. Suppose that the number of sets of M fashions is X, and the total profit of producing two fashions with this batch of cloth is Y yuan. How many production schemes should the garment factory choose to produce this batch of fashion?
2) When the number of M-fashions is fixed, can the profit Y of the factory be maximized? What is the maximum profit?
Answer: 1.5 options. 2. When producing 44 sets of N-fashion, the maximum profit is 3820 yuan.