## How do you calculate HCF?

How to Find HCF?

- Step 1: Write each number as a product of its prime factors. This method is called here prime factorization.
- Step 2: Now list the common factors of both the numbers.
- Step 3: The product of all common prime factors is the HCF ( use the lower power of each common factor)

## What is the HCF of 5 and 7?

1

Answer: GCF of 5 and 7 is 1.

**What is the greatest common factor of 32 24 and 8?**

We found the factors of 8, 32, 24 . The biggest common factor number is the GCF number. So the Greatest Common Factor 8, 32, 24 is 8.

### What is a GCD in math?

In arithmetic: Fundamental theory. …of these numbers, called their greatest common divisor (GCD). If the GCD = 1, the numbers are said to be relatively prime. There also exists a smallest positive integer that is a multiple of each of the numbers, called their least common multiple (LCM).

### How do you solve HCF problems?

How to find HCF by Prime Factorization?

- Step 1: Find the prime factors of the given numbers. In this case, the prime factors of 24 = 2 × 2 × 2 × 3, the prime factors of 36 = 2 × 2 × 3 × 3.
- Step 2: Multiply the prime factors that are common to both the numbers.
- Step 3: Therefore, the HCF of 24 and 36 is 12.

**Why do we calculate HCF?**

The H.C.F. defines the greatest factor present in between given two or more numbers, whereas L.C.M. defines the least number which is exactly divisible by two or more numbers. H.C.F. is also called the greatest common factor (GCF) and LCM is also called the Least Common Divisor.

#### How many prime numbers are there between 1 and 20?

8 prime numbers

There are 8 prime numbers under 20: 2, 3, 5, 7, 11, 13, 17 and 19. The first 10 prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29.

#### What is the Highest common factor of 8 9 and 12?

The highest common factor (HCF) of 8,9 and 12 is 1.

**What is the least common multiple of 16 20 and 30?**

The least common multiple of 16, 20 and 30 is 240.

## What is the greatest common factor of 132 and the square root of 121 using prime factorization?

We found the factors and prime factorization of 121 and 132. The biggest common factor number is the GCF number. So the greatest common factor 121 and 132 is 11.

## What is the GCD of 2 and 4?

2

There are 2 common factors of 2 and 4, that are 1 and 2. Therefore, the greatest common factor of 2 and 4 is 2.

**What is the GCD of 390 and 663?**

Greatest (highest) common factor (divisor)gcf, hcf, gcd (390; 663) = 39 = 3 × 13;The numbers have common prime factors.

### What is the HCF of 351 and 621 by division method?

Answer: The highest common factor of 351 and 621 is 27.

### How do you find the HCF of 108 and 288?

Step 1: Divide 288 (larger number) by 108 (smaller number). Step 2: Since the remainder ≠ 0, we will divide the divisor of step 1 (108) by the remainder (72). Repeat this process until the remainder = 0. ⇒ HCF(108, 288) = 36.

**What is the HCF of 54 288 and 360?**

18

⇒ HCF(54, 288, 360) = 18. Therefore, the HCF of 54, 288 and 360 is 18.

#### How do you calculate HCF and LCM?

The formula that shows the relationship between their LCM and HCF is: LCM (a,b) × HCF (a,b) = a × b. For example, let us take two numbers 12 and 8. Let us use the formula: LCM (12,8) × HCF (12,8) = 12 × 8. The LCM of 12 and 8 is 24; and the HCF of 12 and 8 is 4.