Example 1. The bus fare is 3 yuan for adults, 2 yuan for children and 1 yuan for the disabled. On a certain day, the proportion of adults, children and disabled people is 50:20: 1, and * * * receives 26,740 yuan. How many adults, children and disabled people are there on the bus this day?
Tip: The unit price ratio: adult: child: disabled =3:2: 1.
Number of people: 50:20: 1
1.The ratio of A to B is 7: 4, and A minus 24 equals B. What were the original numbers of A and B?
2. 1 The ratio of class and class 62 is 7: 5, and the two classes go to plant trees together. The saplings are distributed according to the number of people. Results Six classes 1 had six more seedlings. How many saplings did each class get?
1, the armour number is 7x[24÷(7-4)]=7x8=56.
The number b is 56-24=32.
2, * * * * seedlings:
Class 1: 7x[6(7-5)]= 7x 3 = 2 1.
Category II: 2 1-6= 15.
[Exercise] Party A and Party B go the same way. It took Party A 20 minutes and Party B 15 minutes. Now Party A and Party B are walking in opposite directions from two places 840 meters apart. How many meters did A and B walk when they met?
The ratio of the first grid to the second grid of two baskets of fruits is 7: 8. If you take 8kg from the second basket and put it in the first basket, and the second frame is 6kg heavier than the first frame, then find a * * * weight.
Example 2, "Hope Primary School" held a fund-raising activity, and they used the fund-raising money to buy three commodities, namely 30 yuan, 15 yuan and 10 yuan. It is known that the quantity ratio of Party A to Party B is 5:6, and the quantity ratio of Party B to Party C is 4: 1 1. It costs 2 10 yuan more to buy Party C than to buy Party A. ..
Tip: According to the known conditions, the quantity ratio of three commodities can be obtained first.
[Exercise] A mixed candy is made by mixing crisp candy, milk candy and fruit candy in a ratio of 5:4:3. The unit price ratio of crisp candy, milk candy and fruit candy is 1 1:8:7. The mixed sugar is 32.4 yuan per kilogram, and the crisp sugar before mixing is 1: 8: 7.
Example 3, A, B and C are three gears that mesh in turn. A turns four times and B turns three times. When B turned four times, C just turned five times. What is the minimum number of teeth for these three gears?
Tip: According to the known conditions, it is known that the product of the rotational speed and the number of teeth of A, B and C is equal, that is, their rotational speed is inversely proportional to the number of teeth.
Exercise:
1, the base ratio of a, b and c is 4:5:6, and the height ratio is 3:2: 1. Given that the sum of the areas of three parallelograms is 140 square decimeter, what are the areas of the three parallelograms respectively?
2. The area ratio of triangle A, triangle B and triangle C is 8:9: 10, and the height ratio is 2:3:4. What is the corresponding cardinality ratio?
3. The number of students in the fourth and fifth grades of a school is equal, and the ratio of winners to winners in the fourth grade is 1:4, and the ratio of winners to winners in the fifth grade is 2: 7. What is the winning or losing ratio of the two grades?
There are 68 red, white and black balls in the box. The ratio of red ball to white ball is 1:2, and the ratio of white ball to black ball is 3:4. How many red balls are there?