What is the Least Common Multiple of 80 and 100?

Least common multiple or lowest common denominator (lcd) can be calculated in two way; with the LCM formula calculation of greatest common factor (GCF), or multiplying the prime factors with the highest exponent factor.

Least Common Multiple of 80 and 100 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 80 and 100, than apply into the LCM equation.

GCF(80,100) = 20
LCM(80,100) = ( 80 × 100) / 20
LCM(80,100) = 8000 / 20
LCM(80,100) = 400

Least Common Multiple (LCM) of 80 and 100 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 80 and 100. First we will calculate the prime factors of 80 and 100.

Prime Factorization of 80

Prime Factorization of 100

Now multiplying the highest exponent prime factors to calculate the LCM of 80 and 100.

LCM(80,100) = 2⁴ × 5²
LCM(80,100) = 400