GCF and LCM Practice Quiz for 6th Graders (With Solutions)

➕ Topic Summary

The Greatest Common Factor (GCF) is the largest number that divides evenly into two or more numbers. For example, the GCF of 12 and 18 is 6 because 6 is the largest number that divides both 12 and 18 without any remainder. The Least Common Multiple (LCM) is the smallest number that is a multiple of two or more numbers. For example, the LCM of 4 and 6 is 12 because 12 is the smallest number that both 4 and 6 divide into evenly.

Understanding GCF and LCM is super useful in simplifying fractions, solving word problems, and understanding number relationships. This quiz will help you practice finding the GCF and LCM using different methods, such as listing factors/multiples or using prime factorization.

🔤 Part A: Vocabulary

Match the following terms with their correct definitions:

1. Term: Greatest Common Factor (GCF)
2. Term: Least Common Multiple (LCM)
3. Term: Factor
4. Term: Multiple
5. Term: Prime Number

Definitions:

1. A number that divides evenly into another number.
2. The smallest number that is a multiple of two or more numbers.
3. A number that has only two factors: 1 and itself.
4. The largest number that divides evenly into two or more numbers.
5. A number that can be obtained by multiplying a number by an integer.

(Match the terms with the definitions. For example: 1-D, 2-B, etc.)

✍️ Part B: Fill in the Blanks

Complete the following sentences:

The GCF of 24 and 36 is _____. The LCM of 8 and 12 is _____. A _____ number has only two factors, 1 and itself. To find the GCF, you can list all the _____ of each number and find the largest one they have in common. To find the LCM, you can list the _____ of each number until you find the smallest one they share.

🤔 Part C: Critical Thinking

Explain in your own words how finding the GCF and LCM can be helpful in real-life situations. Give at least one example.