Long division is a step-by-step way to divide larger numbers that cannot be solved quickly with basic facts. This cheat sheet helps students organize the dividend, divisor, quotient, and remainder clearly. It also shows how to check an answer so students can find errors before moving on.
Grades 3-5 students use long division to build number sense and prepare for fractions and decimals later.
Key Facts
- In , the dividend is , the divisor is , and the quotient is .
- The long division steps are divide, multiply, subtract, bring down, and repeat until no digits are left.
- A remainder is what is left after division, as in .
- The remainder must always be less than the divisor, so in , a remainder of is not allowed.
- Check a division answer using .
- For , the check is .
- If a digit in the dividend cannot be divided yet, write in the quotient as a placeholder when needed.
- Division and multiplication are inverse operations, so helps solve .
Vocabulary
- Dividend
- The dividend is the number being divided, such as in .
- Divisor
- The divisor is the number you divide by, such as in .
- Quotient
- The quotient is the answer to a division problem, such as in .
- Remainder
- The remainder is the amount left over when the dividend cannot be divided evenly by the divisor.
- Placeholder
- A placeholder is a written in the quotient to keep digits in the correct place value.
- Check
- A check uses multiplication and addition to prove a division answer with .
Common Mistakes to Avoid
- Forgetting to bring down the next digit is wrong because long division must use every digit in the dividend in order.
- Writing a remainder larger than the divisor is wrong because you could divide one more group before stopping.
- Skipping a placeholder in the quotient is wrong because it changes the place value of the answer.
- Subtracting incorrectly after multiplying is wrong because each next step depends on the amount left over.
- Checking with only is wrong when there is a remainder because the check must include .
Practice Questions
- 1 Solve using long division.
- 2 Solve and write the answer with a remainder.
- 3 Find the missing number: , so .
- 4 Explain why the remainder in a division problem must be smaller than the divisor.