| A | B |
| clustering | An estimation method in which a group of numbers close in value are rounded to the same number. |
| expanded form | The sum of the products of each digit and its place value of a number. |
| standard form | Numbers written without exponents. |
| equivalent decimals | Decimals that name the same number. |
| front-end estimation | An estimation method in which the front digits are added or subtracted first, then the digits in the next place value position are added or subtracted. |
| dividend | In a division problem, the number that is being divided. |
| divisor | In a division problem, the number of parts that a number is being divided into. |
| quotient | The answer to a division problem. |
| factor | In a multiplication problem, the numbers being multiplied together. |
| product | The answer to a multiplication problem. |
| addend | In an addition problem, the numbers being added together. |
| sum | The answer to an addition problem. |
| difference | The answer to a subtraction problem. |