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.