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How to write the mathematical formula of senior two?
The math formula for Grade Two is as follows:

First, add up to ten methods.

Good friends1919,2828, hand in hand, 3737 is really close, and 4646 will go together. Make a pair of hands in half.

One plus nine, ten tadpoles, two plus eight, ten old ducks, three plus seven, ten old hens, four plus six, ten golden monkeys,

Five plus five, ten big tigers. Think of 1 when you see 9, 2 when you see 8, 3 when you see 7, and 4 when you see 6. When you see the big corner decimal system, switch the two numbers first.

Second, carry addition is within 20.

1, children should remember "9 to 1", "8 to 2", "7 to 3", "6 to 4" and "5 to 5".

2. The method of making up ten is simple and easy, and the thinking process includes "looking at large numbers, dividing by two (except decimals), dividing by three and adding by four".

3. Look at large numbers, divide them into decimals, make up ten, and add the remainder.

Third, abdication subtraction.

The abdication subtraction should be kept in mind, starting from the unit; Who is not enough to retire, don't forget to add ten to the standard; If the interval is 1, it is best to remember that 0 becomes 10.

Fourth, the subtraction of successive abdications.

When you see 0, go ahead and see which one has it; Borrowed and walked back, 0 is a bit like 9.

Fifth, practice.

Example 1, 8+5=?

Analysis: Add 8+5, and you will think of 2 when you see 8, so 5 can be divided into 2 and 3, and 8 and 2 make up 10,13 =13, so 8+5= 13.