Ctrl+k

Find common factors

A common factor is a whole number that divides each of two or more given whole numbers with no remainder; the shared factors can be identified by listing factor pairs or interpreting equal groups and rectangular arrays. The understanding includes that 1 is a factor of every whole number and that a factor is not the same as a multiple; prime factorization, greatest-common-factor algorithms, and more general work with large numbers are not included.

Detailed Explanation: Find common factors

A common factor is a whole number that divides two numbers evenly, with no remainder.

To find the common factors of 1212 and 1818:

  1. List the factor pairs for 1212:

    • 1×121 \times 12
    • 2×62 \times 6
    • 3×43 \times 4

    So, the factors of 1212 are
    1,2,3,4,6,121, 2, 3, 4, 6, 12.

  2. List the factor pairs for 1818:

    • 1×181 \times 18
    • 2×92 \times 9
    • 3×63 \times 6

    So, the factors of 1818 are
    1,2,3,6,9,181, 2, 3, 6, 9, 18.

  3. Find the numbers that appear in both lists:

1, 2, 3, 61,\ 2,\ 3,\ 6

Therefore, the common factors of 1212 and 1818 are 1,2,3, and 6\boxed{1, 2, 3,\text{ and }6}.

Remember: 11 is a factor of every whole number. A factor divides a number evenly; a multiple is the result of multiplying a number by a whole number.

Learn by doing: Find common factors

Click a topic below to practice the foundational skills you'll need, learn the steps, or master this skill

    Practice with unlimited practice problems

    Finding Greatest Common Factor

      ?