What is the Least Common Multiple of 68 and 80?
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 (LCM) of 68 and 80 is 1360.
LCM(68,80) = 1360
Least Common Multiple of 68 and 80 with GCF Formula
The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 68 and 80, than apply into the LCM equation.
GCF(68,80) = 4
LCM(68,80) = ( 68 × 80) / 4
LCM(68,80) = 5440 / 4
LCM(68,80) = 1360
Least Common Multiple (LCM) of 68 and 80 with Primes
Least common multiple can be found by multiplying the highest exponent prime factors of 68 and 80. First we will calculate the prime factors of 68 and 80.
Prime Factorization of 68
Prime factors of 68 are 2, 17. Prime factorization of 68 in exponential form is:
68 = 22 × 171
Prime Factorization of 80
Prime factors of 80 are 2, 5. Prime factorization of 80 in exponential form is:
80 = 24 × 51
Now multiplying the highest exponent prime factors to calculate the LCM of 68 and 80.
LCM(68,80) = 24 × 171 × 51
LCM(68,80) = 1360