LCM( 6, 12 ) = 12
The formula for finding LCM is
$$ \text{LCM} (a, b) = \frac{ a \cdot b }{ \text{GCD}(a,b)} $$In this example we have: a = 6, b = 12 and GCD(6, 12) = 6.
$$ \text{LCM} (6, 12) = \frac{ 6 \cdot 12 }{ \text{GCD}(6,12)} = \frac{ 72 }{ 6 } = 12 $$