The formula of flat ten method: divide it into decimals and subtract it. Formula for breaking the law of ten: divide a large number by 10, subtract the number and add up the remainder. The formula of filling ten: look at large numbers and decimals, fill ten and the rest. The explanation method of the flat ten method is divided into decimals, which are first reduced by 10, and then the remainder is reduced, and the number is calculated by continuous subtraction.
Ten points: 19 19 Good friend, 2828 holding hands, 3737 really close, 4646 walking together. Make a pair of hands in half. Look at large numbers, divide them into decimals, make up ten, and add up the remainder.
Ten-break method: minus nine plus one minus eight plus two minus seven plus three minus six plus four plus four plus six minus three plus seven minus two plus eight, breaking Osuka decimal. The formula to explain the equal ten method is: "Look at a large number, divide it into decimals, make it ten, and add the remainder." The decimal method is to divide the subtree into two numbers. After subtracting the first number from the subtree, it will be equal to 10, and then subtract the second number from 10 to get the final result.
Q 18-9=？ You can do this by subtracting 8 from 18, leaving 10 and subtracting 1.
The basic principle is: treat 18 as a 10 and an 8, subtract 8 first, and then move 10. 18-9, unit 8 is not enough to subtract 9, so subtract unit 8 first, and it becomes an integer 10. At this time, subtract 1 from this1(because 9=8+ 1), and the answer is 10-65438.
The explanation and examples of the flat ten method are also called the supplementary ten method, which is to turn the carry addition within 20 into the familiar problem of 10 plus several, thus making it difficult and easy.
Expand knowledge:
Ten-step method is a method to calculate the subtraction of abdication within 20, that is, divide the subtrahend into two numbers, and after subtracting the first number from the subtrahend, it is equal to 10. Make up ten laws, break ten laws, and borrow ten laws to level ten laws.
1, break the ten formula
Negative nine plus one, eight plus two, seven plus three, six plus four, five plus five, four plus six, three plus seven, two plus eight. A dozen MINUS nine, a few plus one; Ten MINUS seven, a few plus three; A dozen MINUS five, a few plus five; One dozen MINUS three, several plus seven; A dozen MINUS eight, a few plus two; A dozen MINUS six, a few plus four; A dozen MINUS four, a few plus six; A dozen MINUS two, a few plus eight.
2. Make up ten formulas
Look at large numbers, divide them into decimals, make up ten, and add up the remainder. Clap your hands, children. Let's sing ten songs.
One plus nine, ten little 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.
3. What is the ten-point method?
The method of filling ten is the basic idea of carry addition within 20. By using the method of filling ten, the carry addition within 20 can be transformed into the familiar problem of 10 plus several, which makes it difficult and easy.