The simple calculation method of carry addition is addition principle within 20, no matter how many numbers are added. The fast formula of carry addition within 20 is: several plus nine into ten minus one, several plus eight into ten minus two, several plus seven into ten minus three, and several plus six into ten minus four. Because addition has commutative law, we only need to remember these words. In addition, within 100, first observe the two digits, find out the larger one, and get the answer quickly according to the formula calculation.
Example of "Round First" Algorithm 1.24+44+56
=24+(44+56)
=24+ 100= 124
Solution: Because 44+56= 100 is an integer, it is easier to calculate their sum first, and then add other numbers.
Example 2.53+36+47
=(53+47)+36
= 100+36= 136
Solution: Because 53+47= 100 is an integer, move the symbols before +47 and +36 together and then calculate the sum of 53+47.
Developing good computing habits is an effective way to improve children's computing ability. Help children develop the following good calculation habits, and do the serious calculation habits of "seeing, thinking and calculating".
Calculation is a very serious matter, and we can't be careless, but just some children don't have good study habits. After getting the calculation problem, they can't see the numbers clearly, and they can't see the operation order clearly, so they calculate blindly.
The above is some information about mathematics learning methods, hoping to help everyone.