LCM( 68, 70 ) = 2380
The formula for finding LCM is
$$ \text{LCM} (a, b) = \frac{ a \cdot b }{ \text{GCD}(a,b)} $$In this example we have: a = 68, b = 70 and GCD(68, 70) = 2.
$$ \text{LCM} (68, 70) = \frac{ 68 \cdot 70 }{ \text{GCD}(68,70)} = \frac{ 4760 }{ 2 } = 2380 $$