| A | B |
|---|
| standard form | a number written with one digit for each place |
| word form | a number written in words |
| periods | groups of three places |
| place value | the value of the place of a digit in a number |
| expanded form | a number written to show the value of each digit |
| greater than | representing more of a quantity |
| less than | representing less of a quantity |
| round | to find the nearest ten, hundred, thousand, and so on |
| estimate | to find a number close to an exact amount |
| front-end estimation | an estimation made by computing with only the digits in the greatest place |
| compatible numbers | numbers that are easy to add, subtract, multiply, or divide |
