LCM for 15 and 9

What's the Least Common Multiple (LCM) of 15 and 9?

Answer: LCM of 15 and 9 is 45

(Forty-five)

Finding LCM for 15 and 9 using GCF's of these numbers

The first method to find LCM for numbers 15 and 9 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 15 and 9 is 3, so

LCM = (15 × 9) ÷ 3

LCM = 135 ÷ 3

LCM = 45

Finding LCM for 15 and 9 by Listing Multiples

The second method to find LCM for numbers 15 and 9 is to list out the common multiples for both nubmers and pick the first which matching:

Multiples of 15: 15, 30, 45, 60, 75

Multiples of 9: 9, 18, 27, 36, 45, 54, 63

So the LCM for 15 and 9 is 45

Finding LCM for 15 and 9 by Prime Factorization

Another method to find LCM for numbers 15 and 9 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:

All Prime Factors of 15: 3, 5 (exponent form: 31, 51)

All Prime Factors of 9: 3, 3 (exponent form: 32)

32 × 51 = 45

See Also

About "Least Common Multiple" Calculator

This calculator will help you find the Least Common Multiple (LCM) of two numbers. For example, it can help you find out what's the Least Common Multiple (LCM) of 15 and 9? (The answer is: 45). Select the first number (e.g. '15') and the second number (e.g. '9'). After that hit the 'Calculate' button.
Least Common Multiple (LCM) also known as the Lowest Common Multiple or Smallest Common Multiple of 2 numbers - it is the smallest positive integer that is divisible by both numbers

LCM Table

Number 1Number 2LCM
19
29
39
49
59
69
79
89
999
10990
11999
129
139117
149
159
169144
179153
18918
199171
209180
21963
229198
239207
249
259225
269234
27927
289252
299261
30990

FAQ

What's the Least Common Multiple (LCM) of 15 and 9?

LCM of 15 and 9 is 45