Ten-point method and ten-point method are two commonly used calculation methods in primary school mathematics. They are widely used, which can not only solve simple problems of addition, subtraction, multiplication and division, but also help children develop the ability of quick calculation and logical thinking.
First, add up to ten methods.
The method of ten times ten is the calculation method of dividing a number by the multiple and remainder of 10. The basic idea of this method is to simplify the calculation process and reduce the possibility of errors, thus improving the calculation efficiency. Here is the formula that adds up to ten:
Make up ten, look at one place, it is not enough to borrow ten forward, it is not difficult to count dozens more, and add a few points to the single digit. This formula can help pupils remember the steps of the ten-point method, as follows:
1, split the number to be calculated into multiples of ten and single digits;
2. Single digits less than ten, move forward, and the number is reduced by10;
3. For decimal numbers with carry, retreat by one bit 10, and add the corresponding value to the single digit.
For example, the result of calculating 32+6 can be calculated by rounding up 10:
1, split 32 into 30 and 2 and 6 into 0 and 6;
2. Because 6 is not ten, it will go in two directions and change 6 into16;
3. Because 2 has a carry, subtract 10 from 30 to become 20, and add 2 to the single digit of 16, and the final result is 38.
Second, break the ten laws.
Decimal method is a calculation method that divides a number into integers and differences. The basic idea of this method is to simplify the calculation process and reduce the possibility of errors, thus improving the calculation efficiency. The following is the formula for breaking the ten laws:
Breaking the law of ten, two numbers intersect and the difference is true. It is not difficult to sum according to the law, and it is not difficult to add ten to a small difference. This formula can help primary school students remember the steps to break the ten laws, as follows:
1. Find the difference between two numbers to be calculated;
2. Calculate the sum of the smaller sum and the difference, and remember this sum;
3. If the difference is less than 10, add 10 to the sum of memories to get the final result. Otherwise, you need to divide by ten many times.
For example, the result of calculating 37- 19 can be calculated by breaking ten:
1, find the difference between 37 and 19, that is,18;
2. Because 19 is less than 37, first calculate the sum of 19 and 18 to get 37, remember this sum;
3. Because the difference of 18 is less than 10, add 10 to the memorized sum of 37, and the final result is 47.
In a word, adding ten and breaking ten are two common calculation methods in primary school mathematics. Using these methods, children can complete the calculation of integer addition, subtraction, multiplication and division more quickly and accurately, and improve their mathematical ability and thinking ability.