The formula of filling ten: look at the big number, divide it into small numbers, fill ten, and add the rest. Clap your hands and nod, children. Let's sing ten songs. One plus nine, ten little frogs; Two plus eight, ten old ducks; Three plus seven, ten old chickens; Four plus six, ten macaques; Five plus five, ten big tigers.

Formula for breaking the Ten Laws: minus nine can add one, minus eight can add two, minus seven can add three, minus six can add four, minus five can add five, minus four can add six, minus three can add seven and minus two can add eight. 10 minus nine, plus one; 10 minus seven, plus three; 10 minus five, plus five; 10 minus three and plus seven; 10 minus eight, plus two; 10 minus six, plus four; 10 minus four, plus six; 10 MINUS two, plus eight.

Another formula is to look at large numbers, divide them into decimals, make up ten, and add the remainder. The formula for breaking ten is "minus nine plus one, minus eight plus two, minus seven plus three" and so on.