The application problem of sum and difference in primary schools is 1 1. If the sum of two numbers is 36 and the difference is 22, which number is larger?

2. There are three numbers A, B and C, A plus B equals 252, B plus C equals 197, and C plus A equals 149. What is C?

It costs 10 yuan to buy a mechanical pencil and a pen. It is known that pencils are cheaper than pens, 6 yuan, so how much does it cost to buy pencils?

4. School cleaning, Zhang Juan and Chen Fang cleaned 3 1 piece of glass, knowing that Zhang Juan cleaned 9 pieces less than Chen Fang, how many pieces did Chen Fang clean?

5. A two-digit number is a prime number (1 and it is not divisible by other numbers. Such numbers are called prime numbers. The sum of two numbers is 8, and the difference between the two numbers is 2. What's this number?

The average value of a factory last year and this year was 920,000 yuan, 654.38+10,000 yuan more than last year. What is the output value this year?

7. Three pieces of cloth are 220 meters long, the second one is three times as long as the first one, and the third one is twice as long as the second one. How long is the first paragraph?

8. There are 30 kilograms of apples in basket A and several kilograms of oranges in basket B. If you take out 12 kilograms of oranges from basket B, there are more apples than oranges 10 kilograms. How many kilograms of oranges are there in basket B?

9. Two ships, A and B, carry 623 passengers. If there are 34 passengers in Ship A and 57 passengers in Ship B, the number of passengers in both ships is the same. How many passengers are there in ship A?

10. Zhang Qiang bought a coat, a hat and a pair of shoes with 270 yuan. Coat is more expensive than shoes 140 yuan, coat and shoes are more expensive than hats 2 10 yuan. How much did Zhang Qiang spend on this pair of shoes?

The application problems of sum and difference in primary school are as follows:

There are 72 books in a two-story bookshelf. If you take out nine books from the upper level to the lower level, the upper level has four more books than the lower level. How many books are there on each floor?

Answer:

There are 47 books upstairs and 25 books downstairs.

Later, there were four more books in the upper layer than in the lower layer, so the number of books in the upper layer was 2×9+4=22 ***72.

Subtract the number of the lower layer from the number of the upper layer, which is the number of the upper and lower sides: 72-22 = 50; 50÷2=25。

So there are 25 books on the lower floor and 25+22=47 books on the upper floor.

Summary: To master the applied problem-solving methods, you need to practice a lot of examples to improve your problem-solving ability. This article is for you to do sum and difference exercises, hoping to help children get good grades in math competitions!

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