GCD & LCM Quizzes, Questions & Answers

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GCD Basics

GCD Basics (5)

LCM Basics

LCM Basics (5)

Euclidean Algorithm

Euclidean Algorithm (4)

GCD LCM Practice

GCD LCM Practice (2)

Coprime Numbers

Coprime Numbers (2)

GCD Basics Quizzes

Finding the GCD of Small Numbers

Ready to dive into the world of common factors? In this quiz, you’ll practice finding the greatest common divisor (GCD) of pairs of numbers. From simple fact checks to quick ...

Questions: 10 | Attempts: 64 | Last updated: Jan 20, 2026

Sample Question
What is the GCD of 12 and 18?

2

3

6

12

Prime Factorization and GCD

Want to see how prime numbers connect to the GCD? In this quiz, you’ll break numbers into prime factors and use those building blocks to find the greatest common divisor. You...

Questions: 10 | Attempts: 23 | Last updated: Jan 20, 2026

Sample Question
Find the GCD of 18 and 24 using prime factorization.

2

3

6

12

GCD Master Quiz: Greatest Common Divisor Challenge

The GCD Master Challenge gives you a closer look at how numbers connect through their common factors. Each question guides you to compare values, break them down, and uncover the l...

Questions: 20 | Attempts: 14 | Last updated: May 06, 2026

Sample Question
What is GCD(105, 70)?

35

7

14

21

All GCD Basics Quizzes

LCM Basics Quizzes

Mixed LCM Challenges

Ready to level up? This quiz mixes basic LCM practice, applications, and trickier problems into one set. You’ll use what you’ve learned to solve both straightforward an...

Questions: 20 | Attempts: 57 | Last updated: Jan 19, 2026

Sample Question
LCM of 3 and 4 is:

6

12

24

36

Understanding LCM

What happens when two numbers “line up” at the same multiple? That’s where the Least Common Multiple (LCM) comes in! In this quiz, you’ll practice finding t...

Questions: 20 | Attempts: 25 | Last updated: Jan 19, 2026

Sample Question
What is the LCM of 3 and 5?

10

15

20

30

Word Problems with LCM

Bells ringing, lights blinking, buses arriving—real life is full of repeating events! In this quiz, you’ll solve word problems where the LCM tells you when things happe...

Questions: 20 | Attempts: 17 | Last updated: Jan 19, 2026

Sample Question
Two city fountains spray every 12 minutes and 18 minutes. After how many minutes will both spray together?

24

36

48

54

All LCM Basics Quizzes

Euclidean Algorithm Quizzes

math test-least common multiple

There are two methods that can be confusing for an individual and this is finding the greatest common multiple and the least common multiple. Do you have a strong understanding on ...

Questions: 5 | Attempts: 4196 | Last updated: Mar 04, 2025

Sample Question
What is 5 and 15

30

15

20

45

LL CSET 110 - Number Theory MC

This quiz titled 'LL CSET 110 - Number Theory MC' tests knowledge on the Euclidean Algorithm, number simplification, and properties of numbers formed from primes.

Questions: 15 | Attempts: 146 | Last updated: Oct 23, 2025

Sample Question
5,078 = 150(33)+128 is the first step in finding the greatest common divisor of two numbers. Which of the following is the next step in the Euclidian Algorithm?

150=33(4)+18

128=33(3)+29

150=128(1)+22

5,078=128(39)+86

Euclidean Algorithm Basics

Ever wondered how to quickly find the greatest common divisor (GCD) of two numbers? The Euclidean Algorithm is the oldest (and still one of the fastest!) ways to do it. In this qui...

Questions: 12 | Attempts: 14 | Last updated: Jan 19, 2026

Sample Question
Find GCD(48, 18) using the Euclidean Algorithm.

2

3

6

12

All Euclidean Algorithm Quizzes

GCD LCM Practice Quizzes

GCD and LCM Fundamentals Basics

Want to strengthen your skills with factors and multiples? In this quiz, you’ll practice finding the Greatest Common Divisor (GCD) and Least Common Multiple (LCM) of differen...

Questions: 20 | Attempts: 38 | Last updated: Jan 20, 2026

Sample Question
The GCD of 18 and 24 is:

2

4

6

12

Algebraic Extensions of GCD and LCM

Ready to take GCD and LCM into algebra? In this quiz, you’ll solve equations that connect GCD and LCM to variables, test which values work, and discover how number properties...

Questions: 20 | Attempts: 12 | Last updated: Jan 20, 2026

Sample Question
If GCD(2x, 6) = 2, what is the smallest integer value of x?

1

2

3

4

All GCD LCM Practice Quizzes

Coprime Numbers Quizzes

Identifying and Applying Coprime Numbers

Did you know two numbers don’t have to be prime to be coprime? In this quiz, you’ll explore pairs of numbers that share no factors except 1, test real examples, and con...

Questions: 20 | Attempts: 18 | Last updated: Jan 20, 2026

Sample Question
Which of the following pairs is coprime?

(8, 12)

(15, 25)

(14, 28)

(14, 25)

Coprime Numbers in Algebraic Contexts

Once you know how to spot coprime numbers, it’s time to use them in equations. In this quiz, you’ll solve problems where GCD rules help determine possible values of var...

Questions: 20 | Attempts: 11 | Last updated: Jan 20, 2026

Sample Question
If GCD(12, x) = 1, which x values make (12, x) coprime?

6

9

11

18

All Coprime Numbers Quizzes