What is the Least Common Multiple of 78420 and 78440?

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 78420 and 78440 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 78420 and 78440, than apply into the LCM equation.

GCF(78420,78440) = 20
LCM(78420,78440) = ( 78420 × 78440) / 20
LCM(78420,78440) = 6151264800 / 20
LCM(78420,78440) = 307563240

Least Common Multiple (LCM) of 78420 and 78440 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 78420 and 78440. First we will calculate the prime factors of 78420 and 78440.

Prime Factorization of 78420

Prime Factorization of 78440

Now multiplying the highest exponent prime factors to calculate the LCM of 78420 and 78440.

LCM(78420,78440) = 2³ × 3¹ × 5¹ × 1307¹ × 37¹ × 53¹
LCM(78420,78440) = 307563240