Find closest multiple of $30$ to $51$. We see that $1 \times 30 = 30$ is the nearest. Now subtract $30$ from $51$ to get reminder $21$. Add $1$ to quotient.
Find closest multiple of $30$ to $210$. We see that $7 \times 30 = 210$ is the nearest. Now subtract $210$ from $210$ to get reminder $0$. Add $7$ to quotient.
Since $0$ is less than $30$, stop the division. The reminder is $0$. The topmost line $017$ is the quotient. Remove all zeros at the start of the quotient to get the actual quotient $17$.
