Answer
1 more than the product of 9 and $n$.
Work Step by Step
"The product of" 9 and $n$ expresses the multiplication of 9 and $n$ in $9n$.
"1 more than" expresses the addition of 1 to that term.
Therefore, $1+9n$ can be written as "1 more than the product of 9 and $n$."
