Least Common Multiple of 28 and 45

Created By : Jatin Gogia

Reviewed By : Rajasekhar Valipishetty

Last Updated : Apr 06, 2023

Free LCM Calculator determines the least common multiple (LCM) between 28 and 45 the smallest integer that is 1260 that is divisible by both numbers.

Least Common Multiple (LCM) of 28 and 45 is 1260.

LCM(28,45) = 1260

LCM of 28 and 45

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

LCM of:
and

Least Common Multiple of 28 and 45

LCM of 28 and 45 is 1260

Least common multiple can be found by multiplying the highest exponent prime factors of 28 and 45. First we will calculate the prime factors of 28 and 45.

Prime Factorization of 28


2 28
2 14
7 7
1

Prime factors of 28 are 2,7. Prime factorization of 28 in exponential form is:

28 = 22×71

Prime Factorization of 45


3 45
3 15
5 5
1

Prime factors of 45 are 3,5. Prime factorization of 45 in exponential form is:

45 = 32×51

Now multiplying the highest exponent prime factors to calculate the LCM of 28 and 45.

LCM(28,45) = 22×32×51×71
LCM(28,45) = 1260

Factors of 28

List of positive integer factors of 28 that divides 28 without a remainder.

1, 2, 4, 7, 14, 28

Factors of 45

List of positive integer factors of 45 that divides 45 without a remainder.

1, 3, 5, 9, 15, 45

Least Common Multiple of 28 and 45 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 28 and 45, than apply into the LCM equation.

GCF(28,45) = 1
LCM(28,45) = ( 28 × 45) / 1
LCM(28,45) = 1260 / 1
LCM(28,45) = 1260

Properties of LCM 28 and 45

(i) The LCM of 45 and 28 is associative

LCM of 28 and 45 = LCM of 45 and 28

Related Least Common Multiples of 28

Related Least Common Multiples of 45

Frequently Asked Questions on LCM of 28 and 45

1. What is the LCM of 28 and 45?

Answer: LCM of 28 and 45 is 1260.

2. What are the Factors of 28?

Answer: Factors of 28 are 1, 2, 4, 7, 14, 28. There are 6 integers that are factors of 28. The greatest factor of 28 is 28.

3. What are the Factors of 45?

Answer: Factors of 45 are 1, 3, 5, 9, 15, 45. There are 6 integers that are factors of 45. The greatest factor of 45 is 45.

4. How to Find the LCM of 28 and 45?

Answer:

Least Common Multiple of 28 and 45 = 1260

Step 1: Find the prime factorization of 28

28 = 2 x 2 x 7

Step 2: Find the prime factorization of 45

45 = 3 x 3 x 5

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

LCM = 1260 = 2 x 2 x 3 x 3 x 5 x 7

Step 4: Therefore, the least common multiple of 28 and 45 is 1260.