
Least Common Multiple (LCM) of 21 and 17
The least common multiple (LCM) of 21 and 17 is 357.
What is the Least Common Multiple (LCM)?
The LCM of two integers is the smallest positive integer that is divisible by both numbers. It is often used to find common denominators and solve problems involving periodic events.
Formula for LCM
The LCM of two numbers can be calculated using their GCD:
LCM(a, b) = |a × b| ÷ GCD(a, b)
How to Calculate the LCM of 21 and 17?
First, calculate the GCD of 21 and 17 using the Euclidean algorithm. Then use the formula above to find the LCM.
Step-by-Step GCD Calculation
Step | Calculation |
---|---|
1 | 21 ÷ 17 = 1 remainder 4 |
2 | 17 ÷ 4 = 4 remainder 1 |
3 | 4 ÷ 1 = 4 remainder 0 |
Examples of LCM Calculations
Numbers | LCM |
---|---|
114 and 163 | 18582 |
175 and 115 | 4025 |
67 and 126 | 8442 |
180 and 169 | 30420 |
93 and 24 | 744 |