LCM( 4, 6 ) = 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 = 4, b = 6 and GCD(4, 6) = 2.
$$ \text{LCM} (4, 6) = \frac{ 4 \cdot 6 }{ \text{GCD}(4,6)} = \frac{ 24 }{ 2 } = 12 $$