1 and multiplication of ten digits
Formula: head joint, tail to tail, tail to tail.
For example: 12× 14=?
Formula and algorithm:/kloc-0 /×1=12+4 = 62× 4 = 8.
Answer: 12× 14= 168.
Note: Numbers are multiplied. If two digits are not enough, use 0 to occupy the space. The number multiplication is a two-digit number, remember to add it to the previous one!
This method requires children to try many times, and parents should encourage their children to master it skillfully. This way, children can be one step ahead when they study!
2. Percentage calculation
When calculating the percentage, in fact, "%"can offset two zeros.
For example, when calculating "300 12%", you only need to remove the two zeros after "300" to cross out "%",leaving "3x 12=36". Isn't that easy?
Of course, the principle of this method is actually very simple.
If there is a single digit "0" in both numbers, there is another way: first eliminate the single digits, and then multiply the two numbers to get the answer.
3. Add and subtract scores
Generally speaking, find the least common multiple of two denominators and then calculate. But in fact, just draw a butterfly on the formula.
Multiply the butterfly wings and write them in the antenna. Adding them together is the numerator of the answer, and then multiplying the denominator with each other is the denominator of the answer. Subtraction is the same method, except that the number in the antenna is changed to subtraction.
Butterfly stroke is very suitable for children's playful nature. When children see butterflies, the subconscious will think that learning is a very interesting thing, which can also get twice the result with half the effort in learning mathematics.
4. Multiply fractions by integers
Connecting the denominator and the integer, it is calculated that 24 is 6 times of 4. Then connect the line to the molecule 3, multiply 6 by 3, and the answer 18 can be easily calculated.
This is also a very practical and simple method, and I hope that children can master it skillfully.
5. Multiply two digits by 1 1.
Multiply any two digits by 1 1, separate the ten digits from the single digits, and insert the sum of the ten digits and the single digits in the middle to easily calculate the answer.
6, digital size comparison
Some elementary school students in lower grades can easily use these two comparative symbols.
Parents may wish to let their children remember that the direction of the symbol is like the mouth of a crocodile, of course, the bigger the better!
Does it feel like it after reading it? After learning this, you don't have to worry that children won't compare sizes.
7, 99 multiplication table reciting formula
In fact, many children find it difficult to be multiplied. Today, I will help those children who find it difficult and make them worry-free. As long as you write from 0 to 9 with ten digits and from 9 to 0 with single digits, write a complete table at once. As simple as the picture below.
8. Multiplication of two digits
Multiplication of two digits, especially the mutual multiplication of more than 90, is even more difficult. In fact, there is such a simple skill. For example, 97x96=93 12, just take 100 to subtract the multiplier and the multiplicand, multiply and add the answers respectively, put the multiplied answer in the back, and use 100 to subtract and put it in the front. The answer is exactly the same as the traditional algorithm. Give it a try!