Finding Factors of a Number (Grade 4)
A factor of a number is a whole number that divides it evenly, with no remainder. The factors of 12 are 1, 2, 3, 4, 6, and 12 — because each divides 12 exactly. A reliable way to find all factors is to look for factor pairs: two numbers that multiply to give your number (12 = 1×12, 2×6, 3×4). Listing the pairs catches every factor without missing any.
Understanding finding factors of a number
A factor of a number is a whole number that divides it evenly, with no remainder. The factors of 12 are 1, 2, 3, 4, 6, and 12 — because each divides 12 exactly. A reliable way to find all factors is to look for factor pairs: two numbers that multiply to give your number (12 = 1×12, 2×6, 3×4). Listing the pairs catches every factor without missing any.
Key Idea
A factor of a number is a whole number that divides it evenly, with no remainder. The factors of 12 are 1, 2, 3, 4, 6, and 12 — because each divides 12 exactly. A reliable way to find all factors is to look for factor pairs: two numbers that multiply to give your number (12 = 1×12, 2×6, 3×4). Listing the pairs catches every factor without missing any.
Seeing it in action
Worked example
Find all factors of 12.
Factor pairs: 1×12, 2×6, 3×4.
So the factors are 1, 2, 3, 4, 6, 12.
12 can be arranged as 3 × 4.
Try a few
Factors of 8
Factors of 15
Is 4 a factor of 18?
18 ÷ 4 leaves a remainder.
Factor Fields
A calm number-theory game for factors, multiples, primes, GCF, and LCM.
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