Primary 3 math problems, talk about the solution ideas

1 A is given only one copy.

1) B points to 1 book 6*5=30

2) B points to 2 books 6*10=60

3) B points to 3 books 6*10=60

4) B points to 4 books 6*5=30

5) B to 5 Ben 6

6) B points to 0 Ben 6

2 A was given only two copies.

1) B points to 1 Ben 15 * 4 = 60

2) B points to 2 books 15*6=90

3) B is divided into 3 books 15*4=60

4) B to 4 Ben 15

5) B points to 0 Ben 15

3 A was given only three copies.

1) B points to 1 book 20 * 3 = 60

2) B points to 2 Ben 20 * 3 = 60

3) B points to 3 Ben 20

4) B points to 0 Ben 20

4 A was given only four copies.

1) B points to 0 Ben 15

2) B points to 1 book 15*2=30

3) B points to 2 Ben 15

5 A was given only five copies.

1) B points to 0 Ben 6

2) B points to 1 Ben 6

6 A is divided into 6 books 1

7 A was given only 0 copies.

1) B points to 0 Ben 1

2) B points to 1 Ben 6

3) B points to 2 Ben 15

4) B is divided into 3 books 20

5) B to 4 Ben 15

6) B is divided into 5 Ben 6

7) B is divided into 6 books 1

Total: 192 + 240 + 160 + 60 + 12 + 1 + 58 = 723

Six books are numbered 123456

Here's what it all takes:

A, B, C.

There are 45 kinds in total.

This is an enumeration.

Equation: 2=45

A1B1C4

A1B2C3

A1B3C2

A1B4C1

A2B1C3

A2B2C2

A2B3C1

A3B1C2

A3B2C1

A4B1C1

10 kinds.

The maximum is 3 to the 6th power. The title is not clear.

First, we have to set an unknown.

Then know the circumference of the rectangle c (length + width) 2

You also have to use the area formula s length and width.

The specific answers are as follows.

The answer is 125

The sum of length and width is 30, where the length is 25, the width is 5, and the area is 125, which requires memorization of the formula for the circumference and area of the rectangle.

Length = 60 2 (5+1) 5 = 25 (m).

Width = 60 2 (5+1) 1 = 5 (m).

Area = 25 5 = 125 (sqm).Select C

and times the problem.

Width = 60 2 (5+1) = 5 meters.

Length = 5 5 = 25 meters.

Area = 25 5 = 125 (sqm).

The first car 1100 + 900 kg = 2000 kg = 2 tons.

The second car 200 + 800 + 600 + 400 kg = 2000 kg = 2 tons.

So that the two cars can be transported together.

900 + 1100 = 2000 kg = 2 tons.

200 + 800 + 400 + 600 = 2000 kg = 2 tons, that is, 900 and 1100 for a car.

The remaining four pieces of equipment are one car.

One car loads machines with a weight of 1100kg and 900kg.

The other vehicle is loaded with machines weighing 200kg, 400kg, 600kg and 800kg.

200 + 800 + 600 + 400 = 2000 (kg).

900 + 1100 = 2000 (kg).

In this way, it is enough to separate the two vehicles.

It's very simple, the first car was loaded with 1100 kg and 900 kg, just 2000 kg = 2 tons.

The second car was loaded with 200 kilograms, 800 kilograms, 600 kilograms, 400 kilograms, and exactly 2 tons.

It's just 2 cars.

I can't see the topic clearly, and I can't play it well.

The meaning of the four operations is the basis for solving practical problems, so children should have a deep understanding of the meaning of the four operations. For example, if a child doesn't know "the operation of merging two numbers into one number is called addition", how to answer the question "Xiao Ming has 3 storybooks and Xiaohong has 4 storybooks, how many storybooks do they have?"

This? When answering such a question, let the child know that they are required to have several storybooks, that is, the number of their storybooks is combined, so use addition to calculate.

Subtraction, multiplication, and division also have related meanings, and the meaning of multiplication has different expressions depending on the type of number.

On the basis of understanding these meanings, children's problem-solving ability should be improved by doing certain problems and joining and consolidating.

You have to take your time and let him or her practice this similar question over and over again, sometimes to deepen it and make him (her) accept it, and that's what my teacher taught me.

Do more questions, and you will slowly discover ideas from them.

28*6 4=42 (days) 42-28=14 (days) May is 31 days, so 31-20 = 11 (days) Ye Danqing 14-11 = 3 (days) So he finished reading it on June 3.

6 28 4-28 = 14 days, so it can be read 14 days later, that is, 14 days later on May 20, that is, June 3.

(Chinese + English) 2=93

Chinese + English = 93 2 = 186

Similarly: Chinese + Mathematics + English = 95 3

Mathematics = (Language + Mathematics + English) - (Language + English).

285-186 = 99 points.

Suppose the language is x

Math is y English is z

Because (x z) 2 93

x➕y➕z）➗3＝95

So x z 93 2 186

x➕y➕z＝95✖3＝285

y＝285 ➖186＝99

95 3-93 2 counts out the math score.

Total score in English: 95x3 = 285Total score in English and language: 93x2=186Language, Mathematics, English, Language, English, Mathematics. 285—186=99。

Solution: From the line segment diagram: the number of potatoes in warehouse A after moving 45 bags = the number of potatoes in warehouse B after moving 45 bags.

It turns out that warehouse A has more than warehouse B:

45 bags 2=90 bags.

Because 45 bags were taken out of warehouse A and placed in warehouse B, warehouse A had 45 fewer bags than before, and warehouse B had 45 more bags than before, and now there were the same number of two warehouses, so warehouse A used to have 90 bags more bags than warehouse B.

45 bags were taken out of warehouse A and placed in warehouse B, and the number of bags of potatoes in the two warehouses was exactly the same.

It can be seen as: A-45 = B+45

A-B = 45 + 45 = 90

45 + 45 = 90 bags.

On the other hand, if you have the same number of people, I will give you 45, that is, I have 45 less, you have 45 more, and you have 90 more than me

The number of A is -45 and the number of B is +45

The number of A and the number of B +45+45

Number A - Number B 90

There are 90 more bags of potatoes in warehouse A than in warehouse B.

The third grade may know the "harmony problem", and the third grade Olympiad will talk about this problem.

The first condition, the age difference between the two is 12, yes;

The second condition, the sum of the ages of the two = 35-4 + 3 = 34 So: Huanhuan's age: (34 + 12) divided by 2 = 23 Kaka's age: (34-12) divided by 2 = 11 (or 23-12 = 11).

Age difference: 7+5=12.

Age sum: 35—4+3=34.

Card: (34-12) 2=11 years old.

Huan: 34-11 = 23 years old.