To solve for \( k \) in the equation \( 34k + 38k = 12 \), first combine the like terms on the left side:
\[ 34k + 38k = (34 + 38)k = 72k \]
Thus, the equation simplifies to:
\[ 72k = 12 \]
Next, divide both sides by 72 to isolate \( k \):
\[ k = \frac{12}{72} \]
Now simplify the fraction:
\[ k = \frac{12 \div 12}{72 \div 12} = \frac{1}{6} \]
Therefore, the solution for \( k \) is
\[ \boxed{\frac{1}{6}} \]