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EasyFactors and MultiplesArithmetic

Find the least common multiple of 4 and 6.

The smallest number both divide into.

Try it first: work the problem on paper, then open the solution below and compare each step.
Show the step-by-step solution

Final answer

1212

How we read your problem

Find the least common multiple of the numbers.

Step-by-step solution

  1. Prime factorization of each number

    4=22,6=2×34 = 2^{2},\quad 6 = 2 \times 3
  2. Use the GCF to combine 4 and 6

    lcm⁡(4,6)=4×6gcd⁡(4,6)=242=12\operatorname{lcm}(4, 6) = \frac{4 \times 6}{\gcd(4, 6)} = \frac{24}{2} = 12
  3. Confirm with prime factors

    Take every prime that appears, each with its largest exponent.

    22×3=122^{2} \times 3 = 12

Formulas used

  • LCM from GCF

    lcm⁡(a,b)=∣a⋅b∣gcd⁡(a,b)\operatorname{lcm}(a, b) = \frac{|a \cdot b|}{\gcd(a, b)}

12 is the smallest positive number that every input divides exactly.

Verification

  • 12 ÷ 4 = 3
  • 12 ÷ 6 = 2

About factors and multiples

Prime factorization, greatest common factor and least common multiple.

GCF and LCM

For two positive integers, the product of the GCF and the LCM equals the product of the numbers.

gcd⁡(a,b)⋅lcm⁡(a,b)=ab\gcd(a,b)\cdot\operatorname{lcm}(a,b) = ab

Check your own work