Find closest multiple of $45$ to $54$. We see that $1 \times 45 = 45$ is the nearest. Now subtract $45$ from $54$ to get reminder $9$. Add $1$ to quotient.
Find closest multiple of $45$ to $99$. We see that $2 \times 45 = 90$ is the nearest. Now subtract $90$ from $99$ to get reminder $9$. Add $2$ to quotient.
Since $9$ is less than $45$, stop the division. The reminder is $9$. The topmost line $012$ is the quotient. Remove all zeros at the start of the quotient to get the actual quotient $12$.
