Greatest Common Factor and Least Common Multiple

Math ⇒ Number and Operations

Greatest Common Factor and Least Common Multiple starts at 6 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Greatest Common Factor and Least Common Multiple. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.

See sample questions for grade 8

Explain how to find the LCM of two numbers using their prime factors.

Explain the difference between the greatest common factor and the least common multiple.

Find the GCF and LCM of 21 and 28.

Find the GCF of 32 and 56.

Find the GCF of 48, 60, and 72.

Find the GCF of 84 and 126 using prime factorization.

Find the LCM of 14 and 20.

Find the LCM of 16 and 20.

Find the LCM of 9, 12, and 15.

Find the least common multiple (LCM) of 8 and 12.

If the GCF of two numbers is 1, what are the numbers called?

If the GCF of two numbers is 4 and their LCM is 60, what could the numbers be?

If the GCF of two numbers is 8 and their product is 384, what is their LCM?

If the GCF of two numbers is 9 and their LCM is 72, what is the product of the two numbers?

If the LCM of two numbers is 120 and one of the numbers is 24, what is the smallest possible value of the other number?

If the LCM of two numbers is 42 and their GCF is 7, what could the numbers be?

If the LCM of two numbers is 60 and one of the numbers is 12, what is the smallest possible value of the other number?

If two numbers are relatively prime, what is their GCF?

What is the greatest common factor (GCF) of 18 and 24?

A factory produces two types of widgets. Machine A completes a cycle every 18 minutes, and Machine B completes a cycle every 24 minutes. If both machines start a cycle at 8:00 AM, at what time will they next start a cycle together?