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Least Common Multiple of 20 and 18

Free LCM Calculator determines the least common multiple (LCM) between 20 and 18 the smallest integer that is 180 that is divisible by both numbers.

Least Common Multiple (LCM) of 20 and 18 is 180.

LCM(20,18) = 180

LCM of 20 and 18

Least common multiple or lowest common denominator (LCD) can be calculated in three ways;

LCM of:
and

Least Common Multiple (LCM) of 20 and 18 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 20 and 18. First we will calculate the prime factors of 20 and 18.

Prime Factorization of 20


2 20
2 10
5 5
1

Prime factors of 20 are 2,5. Prime factorization of 20 in exponential form is:

20 = 22×51

Prime Factorization of 18


2 18
3 9
3 3
1

Prime factors of 18 are 2,3. Prime factorization of 18 in exponential form is:

18 = 21×32

Now multiplying the highest exponent prime factors to calculate the LCM of 20 and 18.

LCM(20,18) = 22×32×51
LCM(20,18) = 180

Factors of 20

List of positive integer factors of 20 that divides 20 without a remainder.

1, 2, 4, 5, 10, 20

Factors of 18

List of positive integer factors of 18 that divides 18 without a remainder.

1, 2, 3, 6, 9, 18

Least Common Multiple of 20 and 18 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 20 and 18, than apply into the LCM equation.

GCF(20,18) = 2
LCM(20,18) = ( 20 × 18) / 2
LCM(20,18) = 360 / 2
LCM(20,18) = 180

Properties of LCM 20 and 18

(i) The LCM of 18 and 20 is associative

LCM of 20 and 18 = LCM of 18 and 20

Frequently Asked Questions on LCM of 20 and 18

1. What is the LCM of 20 and 18?

Answer: LCM of 20 and 18 is 180.

2. What are the Factors of 20?

Answer: Factors of 20 are 1, 2, 4, 5, 10, 20. There are 6 integers that are factors of 20. The greatest factor of 20 is 20.

3. What are the Factors of 18?

Answer: Factors of 18 are 1, 2, 3, 6, 9, 18. There are 6 integers that are factors of 18. The greatest factor of 18 is 18.

4. How to Find the LCM of 20 and 18?

Answer:

Least Common Multiple of 20 and 18 = 180

Step 1: Find the prime factorization of 20

20 = 2 x 2 x 5

Step 2: Find the prime factorization of 18

18 = 2 x 3 x 3

Step 3: Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the lcm:

LCM = 180 = 2 x 2 x 3 x 3 x 5

Step 4: Therefore, the least common multiple of 20 and 18 is 180.