Least Common Multiple of 8 and 15

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

• Least Common Multiple of 8 and 15 by Prime method
• Least Common Multiple of 8 and 15 with GCF Formula

Least common multiple can be found by multiplying the highest exponent prime factors of 8 and 15. First we will calculate the prime factors of 8 and 15.

Prime Factorization of 8

Prime factors of 8 are 2. Prime factorization of 8 in exponential form is:

8 = 2³

Prime Factorization of 15

Prime factors of 15 are 3,5. Prime factorization of 15 in exponential form is:

15 = 3¹×5¹

Now multiplying the highest exponent prime factors to calculate the LCM of 8 and 15.

LCM(8,15) = 2³×3¹×5¹
LCM(8,15) = 120

Factors of 8

List of positive integer factors of 8 that divides 8 without a remainder.

1, 2, 4, 8

Factors of 15

List of positive integer factors of 15 that divides 15 without a remainder.

1, 3, 5, 15

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 8 and 15, than apply into the LCM equation.

GCF(8,15) = 1
LCM(8,15) = ( 8 × 15) / 1
LCM(8,15) = 120 / 1
LCM(8,15) = 120

(i) The LCM of 15 and 8 is associative

LCM of 8 and 15 = LCM of 15 and 8

1. What is the LCM of 8 and 15?

Answer: LCM of 8 and 15 is 120.

2. What are the Factors of 8?

Answer: Factors of 8 are 1, 2, 4, 8. There are 4 integers that are factors of 8. The greatest factor of 8 is 8.

3. What are the Factors of 15?

Answer: Factors of 15 are 1, 3, 5, 15. There are 4 integers that are factors of 15. The greatest factor of 15 is 15.

4. How to Find the LCM of 8 and 15?

Answer:

Least Common Multiple of 8 and 15 = 120

Step 1: Find the prime factorization of 8

8 = 2 x 2 x 2

Step 2: Find the prime factorization of 15

15 = 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 = 120 = 2 x 2 x 2 x 3 x 5

Step 4: Therefore, the least common multiple of 8 and 15 is 120.