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Division · level 2

Division by factors

Split the divisor into two easy factors and divide twice. Two short divisions beat one long one every time.

Worked example: 3,528 ÷ 24

÷ 6588
÷ 4147

Step by step

  1. 1

    Factorise the divisor

    24 = 6 × 4

  2. 2

    Divide by 6

    3,528 ÷ 6 = 588

  3. 3

    Divide by 4

    588 ÷ 4 = 147

3,528 ÷ 24 = 147

The theory behind it

Intuition

Dividing by factors turns one hard division into two easy ones: ÷12 is ÷3 then ÷4. Order the factors so the first division stays clean.

Common pitfalls

  • ×Multiplying by a factor instead of dividing on the second step.
  • ×Choosing factors that create repeating decimals early.

In the interview

Unit economics is division: cost per user, revenue per store, payback in years.