Test out your knowledge of adding 3-digit and 1-digit numbers together with this quiz, then read on to complete the page. It's really helpful to understand hundreds, tens and ones when adding ...

Write a 2 in the ones column and write a 10 in the tens column as a 1 below the column. Slide 1 of 4, , Start from the ones column: 3 + 9 = 12. This needs regrouping, so 12 can be regrouped to 10 + 2.