What is the Least Common Multiple of 7978 and 7990?

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 7978 and 7990 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 7978 and 7990, than apply into the LCM equation.

GCF(7978,7990) = 2
LCM(7978,7990) = ( 7978 × 7990) / 2
LCM(7978,7990) = 63744220 / 2
LCM(7978,7990) = 31872110

Least Common Multiple (LCM) of 7978 and 7990 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 7978 and 7990. First we will calculate the prime factors of 7978 and 7990.

Prime Factorization of 7978

Prime Factorization of 7990

Now multiplying the highest exponent prime factors to calculate the LCM of 7978 and 7990.

LCM(7978,7990) = 2¹ × 3989¹ × 5¹ × 17¹ × 47¹
LCM(7978,7990) = 31872110