Exploring the Greatest Common Factor

This video tutorial explains the concept of the greatest common divisor (GCD) or greatest common factor (GCF), demonstrating how to find it through examples. It covers the process of listing factors of numbers and identifying common factors, with examples including pairs like 12 and 8, 25 and 20, 5 and 12, and 6 and 12. The video also introduces the term 'relatively prime' for numbers whose GCD is 1.

What does GCD stand for in mathematical terms?

• General Common Denominator

• Greatest Common Divisor

• General Calculated Divisor

• Greatest Collective Denominator

Which of the following is a factor of both 12 and 8?

• 3

• 4

• 5

• 7

What is the GCD of 12 and 8?

• 6

• 3

• 2

• 4

Which number is a factor of 25 but not of 20?

• 5

• 3

• 2

• 10

What is the GCD of 25 and 20?

• 1

• 5

• 10

• 25

What does it mean if two numbers are relatively prime?

• They share multiple common factors.

• They share all the same factors.

• They have no common factors other than 1.

• They are both prime numbers.

What is the GCD of 5 and 12?

• 1

• 2

• 12

• 5

Which of the following is a common factor of both 6 and 12?

• 2

• All of the above

• 1

• 3

What is the GCD of 6 and 12?

• 3

• 6

• 12

• None of the above

Which statement is true when a number is divisible by another?

• It is always the smaller number.

• It can be either the smaller or the larger number.

• It is always the larger number.

• None of the above