LCM( 12, 36 ) = 36
The formula for finding LCM is
$$ \text{LCM} (a, b) = \frac{ a \cdot b }{ \text{GCD}(a,b)} $$In this example we have: a = 12, b = 36 and GCD(12, 36) = 12.
$$ \text{LCM} (12, 36) = \frac{ 12 \cdot 36 }{ \text{GCD}(12,36)} = \frac{ 432 }{ 12 } = 36 $$