36-7=29 years old

Cause analysis: If 63 is taken as 36, it means that you have read (copied) the wrong number.

There are three classes in Grade Two. Class 2 has five more people than class/kloc-0 and class 3 has three more people than class/kloc-0. The number of students in Class Three is the least.

Error analysis: the relationship between quantity and size cannot be correctly understood.

3. Daqing shot 135 ball, Xiaoqing shot less than Daqing, Xiaohong shot more than Daqing.

1) How many photos can Xiaoqing take at most? 135- 10=225 (piece)

2) How many times does Xiaohong shoot at least? 135+10 =145 (pieces)

Cause analysis: I can't understand the meaning of "maximum" and "minimum" accurately.

4. To do the addition formula, Xiao Ming regards 6 in one plus digit as 9 and 1 in ten digits as 7 to get 604. The correct number is (588).

Error analysis: I don't understand that the numbers that are misread by one digit and ten digits respectively are actually redundant numbers, but directly subtract 16.

There are three ropes 60 meters long, one of which is 5 meters longer than the shortest one and 5 meters shorter than the longest one. How long is the longest one? What is the shortest meter? This question is a supplement to the examination paper.

The longest is 60 meters and the shortest is 5 meters.

Cause analysis: suppose three ropes are the same length, 60÷3=20, the longest is 20+5=25, and the shortest is 20-5= 15.

6. Each sling is 5 meters long. Is it enough to cut a 42-meter rope into eight slings?

43÷5=8 (root) ... 3 (meter) is not enough.

Cause analysis: If 42 is regarded as 43, the algorithm is correct and the conclusion is wrong.

There are 60 people in the class, of which the number of boys is twice that of *. Do you know how many boys there are and how many *?

Cause analysis: This is a sum multiple problem. You will understand after reading the third grade.

In order to attract customers, the supermarket is going to make a gift box with the combination of "2 boxes of milk and 3 boxes of yogurt" and then sell it. How many gift boxes can it make?

Commodity name and quantity

Milk 18 boxes

24 boxes of yogurt

Can be made into 20 gift boxes.

Error analysis: First, two boxes of milk can be divided into nine parts, and three boxes of yogurt can be divided into eight parts. Only a few combinations can be selected, and the answer should be eight gift boxes. Peanuts and candy can be used in combination with the actual operation.

9, 18 a bottle of calcium tablets, Xiaohui insists on eating it every day, once in the morning and three tablets each time. How many days can a bottle of medicine last?

18÷3=6 (days)

Cause analysis: I didn't understand the meaning of multiplication contained in "morning and evening three films" 2×3.

10. A car has four wheels and a spare tire. Now there are 38 wheels. How many such cars can you load? How many wheels are left?

38÷4=9 (vehicle) ... 2 (vehicle)

Cause analysis: I failed to correctly understand the meaning of "a car has four wheels and a spare tire" and trained to improve students' reading comprehension ability.