What is the Least Common Multiple of 780 and 790?

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 780 and 790 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 780 and 790, than apply into the LCM equation.

GCF(780,790) = 10
LCM(780,790) = ( 780 × 790) / 10
LCM(780,790) = 616200 / 10
LCM(780,790) = 61620

Least Common Multiple (LCM) of 780 and 790 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 780 and 790. First we will calculate the prime factors of 780 and 790.

Prime Factorization of 780

Prime Factorization of 790

Now multiplying the highest exponent prime factors to calculate the LCM of 780 and 790.

LCM(780,790) = 2² × 3¹ × 5¹ × 13¹ × 79¹
LCM(780,790) = 61620