Find closest multiple of $50$ to $77$. We see that $1 \times 50 = 50$ is the nearest. Now subtract $50$ from $77$ to get reminder $27$. Add $1$ to quotient.
Find closest multiple of $50$ to $270$. We see that $5 \times 50 = 250$ is the nearest. Now subtract $250$ from $270$ to get reminder $20$. Add $5$ to quotient.
Since $20$ is less than $50$, stop the division. The reminder is $20$. The topmost line $015$ is the quotient. Remove all zeros at the start of the quotient to get the actual quotient $15$.
