What is the Least Common Multiple of 5 and 9?
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 5 and 9 is 45.
LCM(5,9) = 45
Least Common Multiple of 5 and 9 with GCF Formula
The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 5 and 9, than apply into the LCM equation.
GCF(5,9) = 1
LCM(5,9) = ( 5 × 9) / 1
LCM(5,9) = 45 / 1
LCM(5,9) = 45
Least Common Multiple (LCM) of 5 and 9 with Primes
Least common multiple can be found by multiplying the highest exponent prime factors of 5 and 9. First we will calculate the prime factors of 5 and 9.
Prime Factorization of 5
Prime factors of 5 are 5. Prime factorization of 5 in exponential form is:
5 = 51
Prime Factorization of 9
Prime factors of 9 are 3. Prime factorization of 9 in exponential form is:
9 = 32
Now multiplying the highest exponent prime factors to calculate the LCM of 5 and 9.
LCM(5,9) = 51 × 32
LCM(5,9) = 45