Find closest multiple of $400$ to $600$. We see that $1 \times 400 = 400$ is the nearest. Now subtract $400$ from $600$ to get reminder $200$. Add $1$ to quotient.
Find closest multiple of $400$ to $2000$. We see that $5 \times 400 = 2000$ is the nearest. Now subtract $2000$ from $2000$ to get reminder $0$. Add $5$ to quotient.
Since $0$ is less than $400$, stop the division. The reminder is $0$. The topmost line $0015$ is the quotient. Remove all zeros at the start of the quotient to get the actual quotient $15$.
