Long Division Formula

Long division is a step-by-step method for dividing large numbers by breaking the problem into a series of easier steps: divide, multiply, subtract, bring.

The Formula

dividend=divisor×quotient+remainder\text{dividend}=\text{divisor}\times\text{quotient}+\text{remainder}

When to use: Long division is like distributing items into groups one place value at a time. If you have 156 stickers to share among 12 friends, you first figure out how many groups of 12 fit in 156 by working from the biggest place value down: how many 12s in 15? Then bring down the next digit and repeat.

Quick Example

156÷12=13because 12×13=156156 \div 12 = 13 \quad \text{because } 12 \times 13 = 156

Notation

Every long-division answer should satisfy dividend = divisor times quotient plus remainder.

What This Formula Means

Long division is a step-by-step method for dividing large numbers by breaking the problem into a series of easier steps: divide, multiply, subtract, bring down, and repeat. It produces a quotient and possibly a remainder.

Long division is like distributing items into groups one place value at a time. If you have 156 stickers to share among 12 friends, you first figure out how many groups of 12 fit in 156 by working from the biggest place value down: how many 12s in 15? Then bring down the next digit and repeat.

Formal View

a=bq+ra = bq + r where aa is the dividend, bb is the divisor, q=a/bq = \lfloor a/b \rfloor is the quotient, and 0r<b0 \leq r < b is the remainder (Division Algorithm)

Worked Examples

Example 1

easy
Compute 846÷6846 \div 6.

Answer

141141

First step

1
Divide 8 by 6: quotient digit 1, remainder 86=28 - 6 = 2. Bring down 4 to get 24.

Full solution

  1. 2
    Divide 24 by 6: quotient digit 4, remainder 0. Bring down 6 to get 6.
  2. 3
    Divide 6 by 6: quotient digit 1, remainder 0.
  3. 4
    Result: 846÷6=141846 \div 6 = 141.
Long division works digit by digit from left to right: divide, multiply, subtract, bring down, and repeat.

Example 2

medium
Compute 1573÷111573 \div 11.

Example 3

easy
Compute 988÷4988 \div 4 step by step.

Common Mistakes

  • Dropping a digit without asking what place it represents — say hundreds, tens, or ones at each step.
  • Writing a remainder bigger than the divisor — keep dividing until the remainder is smaller than the divisor.
  • Not checking by multiplication — verify divisor times quotient plus remainder equals the dividend.

Why This Formula Matters

Long division is where many students start performing steps without meaning. Understanding it as repeated grouping by place value makes remainders, zeros in the quotient, and estimation checks much safer. Recognizing it by "Can I check the answer by multiplying the quotient by the divisor?" — rather than by familiar numbers — is what lets a student tell it apart from basic division fact and multi-digit multiplication in a mixed problem set.

Frequently Asked Questions

What is the Long Division formula?

Long division is a step-by-step method for dividing large numbers by breaking the problem into a series of easier steps: divide, multiply, subtract, bring down, and repeat. It produces a quotient and possibly a remainder.

How do you use the Long Division formula?

Long division is like distributing items into groups one place value at a time. If you have 156 stickers to share among 12 friends, you first figure out how many groups of 12 fit in 156 by working from the biggest place value down: how many 12s in 15? Then bring down the next digit and repeat.

What do the symbols mean in the Long Division formula?

Every long-division answer should satisfy dividend = divisor times quotient plus remainder.

Why is the Long Division formula important in Math?

Long division is where many students start performing steps without meaning. Understanding it as repeated grouping by place value makes remainders, zeros in the quotient, and estimation checks much safer. Recognizing it by "Can I check the answer by multiplying the quotient by the divisor?" — rather than by familiar numbers — is what lets a student tell it apart from basic division fact and multi-digit multiplication in a mixed problem set.

What do students get wrong about Long Division?

The procedure for long division is the easy part; the trap is dropping a digit without asking what place it represents. Asking "Can I check the answer by multiplying the quotient by the divisor?" first is what keeps a correct-looking calculation from being attached to the wrong concept.

What should I learn before the Long Division formula?

Before studying the Long Division formula, you should understand: division, subtraction, multiplication.

Want the Full Guide?

This formula is covered in depth in our complete guide:

Polynomial Long Division: Step-by-Step Method with Examples →