There is a pattern to how the numbers are written from 1 to 100, but we can’t hear a regular pattern in the way we say the numbers until we get to the number 20. For example, count aloud from 31 ...

Start from the ones column: 3 + 9 = 12. Write a 2 in the ones column and carry 10 to the tens column by writing ... 129 is the same as 129 + 345. Key words - look out for these words in problems ...