Free LCM Calculator determines the least common multiple (LCM) between 16 and 20 the smallest integer that is 80 that is divisible by both numbers.

Least Common Multiple (LCM) of 16 and 20 is **80**.

LCM(16,20) = 80

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

- Least Common Multiple of 16 and 20 by Prime method
- Least Common Multiple of 16 and 20 with GCF Formula

Least common multiple can be found by multiplying the highest exponent prime factors of 16 and 20. First we will calculate the **prime factors of 16 and 20**.

**Prime Factorization of 16**

2 | 16 |

2 | 8 |

2 | 4 |

2 | 2 |

1 |

Prime factors of 16 are 2. Prime factorization of **16** in exponential form is:

16 = 2^{4}

**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 = 2^{2}×5^{1}

Now multiplying the highest exponent prime factors to calculate the **LCM of 16 and 20**.

LCM(16,20) = 2^{4}×5^{1}

LCM(16,20) = 80

**Factors of 16**

List of positive integer factors of 16 that divides 16 without a remainder.

1, 2, 4, 8, 16

**Factors of 20**

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

1, 2, 4, 5, 10, 20

The formula of **LCM** is LCM(a,b) = ( a × b) / GCF(a,b).

We need to calculate greatest common factor 16 and 20, than apply into the LCM equation.

GCF(16,20) = 4

LCM(16,20) = ( 16 × 20) / 4

LCM(16,20) = 320 / 4

LCM(16,20) = 80

(i) The LCM of 20 and 16 is associative

LCM of 16 and 20 = LCM of 20 and 16

1. What is the LCM of 16 and 20?

Answer: LCM of 16 and 20 is 80.

2. What are the Factors of 16?

Answer: Factors of 16 are 1, 2, 4, 8, 16. There are 5 integers that are factors of 16. The greatest factor of 16 is 16.

3. 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.

4. How to Find the LCM of 16 and 20?

Answer:

Least Common Multiple of 16 and 20 = 80

Step 1: Find the prime factorization of 16

16 = 2 x 2 x 2 x 2

Step 2: Find the prime factorization of 20

20 = 2 x 2 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 = 80 = 2 x 2 x 2 x 2 x 5

Step 4: Therefore, the least common multiple of 16 and 20 is 80.