GCD and LCM Calculator
Calculate the Greatest Common Divisor (GCD) and Least Common Multiple (LCM) of numbers.
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About GCD & LCM
Calculate the Greatest Common Divisor (GCD) and Least Common Multiple (LCM) of numbers.
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How the GCD and LCM Calculator Works
The Greatest Common Divisor (GCD) is the largest number that divides both numbers evenly. The Least Common Multiple (LCM) is the smallest positive number divisible by both. These concepts are fundamental in simplifying fractions and number theory.
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Enter First Number
Input the first positive integer
- 2
Enter Second Number
Input the second positive integer
- 3
Calculate GCD
The calculator uses the Euclidean algorithm to find GCD
- 4
Calculate LCM
LCM is computed using: LCM = |a x b| / GCD
Use Cases
Simplifying Fractions
Divide numerator and denominator by their GCD to reduce fractions
Finding Common Denominators
Use LCM to find the least common denominator when adding fractions
Scheduling Problems
Determine when periodic events will coincide
Number Theory
Solve problems in algebra and cryptography
Tips
- 1
GCD is always less than or equal to the smaller number
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LCM is always greater than or equal to the larger number
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GCD(a,b) x LCM(a,b) = |a x b|
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If GCD = 1, the numbers are coprime (relatively prime)
Common Mistakes
Confusing GCD and LCM - GCD divides the numbers, numbers divide LCM
Using GCD/LCM with negative numbers - always use absolute values
Assuming LCM = a x b always - this is only true when GCD = 1
Forgetting that GCD(a, 0) = a
Frequently Asked Questions
What is the Greatest Common Divisor (GCD)?
What is the Least Common Multiple (LCM)?
What is the Euclidean algorithm?
How are GCD and LCM related?
What does coprime mean?
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