Concise memory formula

19 19 years of good friends,

Hand in hand,

3737 is so close,

Let's go together, four, four, six, six.

Make a pair of hands in half.

Look at large numbers, divide them into decimals, make up ten, and add up the remainder. Remember large numbers in your mind and decimals in your hand. One plus nine, ten tadpoles, two plus eight, ten old ducks, three plus seven, ten old hens, four plus six, ten golden monkeys, five plus five, and ten big tigers.

Think of 1 when you see 9, 2 when you see 8, 3 when you see 7, and 4 when you see 6. When you see the big corner decimal system, switch the two numbers first.

These are the skills of quick oral calculation in grade three. As long as children do some exercises, they will soon master these quick language skills. With the foundation of oral calculation, children will not be particularly hard when they study mathematics in the next step. Therefore, parents should never relax their children's oral arithmetic practice in senior one.