To factor the expression \( 12s + 42 \), we need to find the greatest common factor (GCF) of the two terms.
The GCF of \( 12 \) and \( 42 \) is \( 6 \).
Now we can factor out \( 6 \) from the expression:
\[ 12s + 42 = 6(2s) + 6(7) = 6(2s + 7) \]
Thus, the factored form of \( 12s + 42 \) is:
\[ \boxed{6(2s + 7)} \]
where \( 6 \) is the whole number greater than 1.