Three, seven, three, seven, seven, seven, so close, let's come together four, four, six, six,
50-50% hands, ten friends remember.
Math nursery rhymes of junior students;
A, two digits plus or minus integer ten or digits of oral arithmetic.
Ten plus ten, one plus one,
The digits add up to ten, ten plus one;
Ten MINUS ten, one MINUS one,
There are not enough places, and there are ten places.
Second, the addition formula name memory
Every item in the formula has a name, and everyone writes it down.
Both sides of the plus sign are called addends, and the equal sign is called sum.