Let us know what is GCF of 10 15 and 25. The greatest common factor (GCF) of some numbers is the largest number that is equally divisible by all numbers. For example, the GCF of 10, 15 and 25 is **5** .

Similarly, what is GCF 6? The greatest common factor (GCF or GCD or HCF) of the set of whole numbers is the greatest positive integer that divides evenly into all **numbers with zero** remainder. For example, GCF = 6 for the set of numbers 18, 30 and 42. (GCF of 10 15 and 25)

What are the factors of 21? **factors of 21**

- 21: Factors 1, 3, 7 and 21.
- Negative factors of 21: -1, -3, -7 and -21.
- 21: 3, prime factors of 7
- Prime factorization of 21: 3 × 7 = 3 × 7.
- The sum of the factors of 21:32.

What is the GCF of 20 and 15? The GCF of 15 and 20 is **5** . To calculate the GCF (Greatest Common Factor) of 15 and 20, we need to factor each number (15 = 1, 3, 5, 15; 20 = 1, 2, 4, 5, 10, 20) and the most Choose the greater factor that exactly divides both 15 and 20, i.e. 5.

Second what is the GCF of 20? The prime factors of 20 are 2 x 2 x 5. No prime factors are the same in 9 and 20. The greatest common factor is **1** .

**What is the GCF of 12 and 15?**

Answer: GCF of 12 and 15 is **3** .

So what is the GCF of 12 and 21? Answer: GCF of 12 and 21 is **3** .

What is a factor of 15? Factor 15 by prime factorization

The factors of 15 are **1, 3, 5, and 15** .

**What is GCF for 21?**

The GCF of 21 and 30 is **3** . To calculate the greatest common factor of 21 and 30, we need to factor each number (21 = 1, 3, 7, 21; 30 = 1, 2, 3, 5, 6, 10, 15, 30). must be factored. And choose the greatest factor that exactly divides both 21 and 30, i.e. 3.

How do you make 21? We know that multiplying 1 by 21 gives 21, so they are both factors. 2 is not a factor of 21, because we cannot multiply it by any other whole number. 21.3 is a factor of 21, because it multiplies by 7 to make 21. So the factors of 21 are **1, 3, 7 and 21** .

How do you find GCF?

To find the GCF of a set of numbers, **list all the factors of each number** . The largest factor that appears in each list is GCF. For example, to find the GCF of 6 and 15, first list all the factors of each number. Because 3 is the largest factor that appears in both lists, 3 is the GCF of 6 and 15.

What is the GCF of 21 and 35? Answer: The GCF of 21 and 35 is **7** .

**What is the fastest way to find GCF?**

What is the GCF of 21?

The GCF of 21 and 30 is **3** . To calculate the greatest common factor of 21 and 30, we need to factor each number (21 = 1, 3, 7, 21; 30 = 1, 2, 3, 5, 6, 10, 15, 30). must be factored. And choose the greatest factor that exactly divides both 21 and 30, i.e. 3.

How do you do GCF? **Here’s how to find the GCF of a set of numbers using prime factors:**

- List the prime factors of each number.
- Circle each common prime factor – that is, every prime factor that is a factor of every number in the set.
- Multiply all rounded numbers. The result is GCF.

What is the common factor of 21 and 35? 2 and 21 have 35 common factors, which are **1 and 7** . Therefore, the greatest common factor of 21 and 35 is 7.

**What are the factors of 21 and 18?**

The factors of 18 and 21 are **1, 2, 3, 6, 9, 18 and 1, 3, 7, 21** respectively.

What are the factors of 20? **factors of 20**

- 20: Factors 1, 2, 4, 5, 10 and 20.
- Negative factors of 20: -1, -2, -4, -5, -10 and -20.
- 20: prime factors of 2, 5
- Prime factorization of 20: 2 × 2 × 5 = 2
^{2 }× 5. - The sum of the factors of 20:42.

What is the GCF of 14 and 21?

Answer: The GCF of 14 and 21 is **7** .

What is the HCF of 20 and 15? Answer: HCF of 15 and 20 is **5** .

**Which of the following number is not a factor of 21?**

Answer: **6** is not a factor of 21.

What is the least to greatest factor of 15? 15 has four factors, i.e. 1, 3, 5 and 15. Therefore, the smallest factor is 1 and the largest factor is **15, itself** . The sum of all the factors of 15 is equal to 24.

What are the multiples of 15?

The multiples of 15 are **15, 30, 45 60, 75, 90, 105** .