Review: place value and shapes
A 3-digit number has hundreds, tens and ones. In 436 the 4 is 4 hundreds, which is 400. The 3 is 3 tens, which is 30. The 6 is 6 ones. In expanded form, 436 = 400 + 30 + 6. To compare two numbers, start with the hundreds. If they are the same, compare the tens, then the ones. 354 > 345 because the hundreds are equal and 5 tens is more than 4 tens. To add with regrouping, 10 ones make a new ten: 47 + 36 gives 13 ones, so write 3 and carry 1 ten, and the answer is 83. Shapes: triangles have 3 sides, quadrilaterals 4, pentagons 5 and hexagons 6.
| Hundreds | Tens | Ones |
|---|---|---|
| 4 | 3 | 6 |
| 400 | 30 | 6 |
| Number | Hundreds | Tens | Ones |
|---|---|---|---|
| 354 | 3 | 5 | 4 |
| 345 | 3 | 4 | 5 |
Number cards. Write the digits 0 to 9 on ten cards. Pick three and make the biggest 3-digit number you can, then the smallest one. Say each number and its expanded form. Compare your numbers with someone else’s using greater than and less than.