Question

Four more than a number is no more than thirteen

Answer 1

If x+4>13 then it would be x>9

Answer 2

Four more than a number = x + 4;
No more than means using < in the equation;
So $x+4\ \textgreater \ 13$ is your equation.
$x+4\ \textgreater \ 13\\ x\ \textgreater \ 9$