jmc

If the hundreds digit is $1,$ there are $3$ possible numbers for the tens digit: $2,$ $3,$ and $4.$ Any number greater than $4$ is impossible because the units digit must be a multiple of the tens digit. Therefore, we have $124,$ $126,$ $128,$ $136,$ $139,$ and $148.$

If the hundreds digit is $2,$ there is only $1$ possible number for the tens digit: $4$ because any number greater than $4$ would have a multiple that has two digits. Therefore, we have $248.$

We cannot have any number with a hundreds digit larger than $2$. Therefore, there are $6+1=\boxed{7}$ possible numbers.