Three processes A, B and C each execute a loop of 100 iterations. In each iteration of the loop, a process performs a single computation that requires $t_c$ CPU milliseconds and then initiates a single I/O operation that lasts for $t_{io}$ milliseconds. It is assumed that the computer where the processes execute has sufficient number of I/O devices and the OS of the computer assigns different I/O devices to each process. Also, the scheduling overhead of the OS is negligible. The processes have the following characteristics: The processes A, B, and C are started at times 0, 5 and 10 milliseconds respectively, in a pure time sharing system (round robin scheduling) that uses a time slice of 50 milliseconds. The time in milliseconds at which process C would complete its first I/O operation is _________.

Let us trace the Round Robin execution with a time quantum of $50\text{ ms}$:

• $t = 0\text{ ms}$: Process A arrives with CPU burst $100\text{ ms}$. Ready Queue: $[\text{A}]$. Process A executes for its time slice from $t = 0$ to $50$.

• During this time, Process B arrives at $t = 5\text{ ms}$ and Process C arrives at $t = 10\text{ ms}$.

• $t = 50\text{ ms}$: Process A's time slice expires (A has $50\text{ ms}$ CPU remaining). A is preempted and added to the tail of the queue. Ready Queue: $[\text{B}, \text{C}, \text{A}]$.

• $t = 50\text{ to } 100\text{ ms}$: Process B executes for $50\text{ ms}$ (B has $300\text{ ms}$ remaining). Ready Queue: $[\text{C}, \text{A}, \text{B}]$.

• $t = 100\text{ to } 150\text{ ms}$: Process C executes for $50\text{ ms}$ (C has $150\text{ ms}$ remaining). Ready Queue: $[\text{A}, \text{B}, \text{C}]$.

• $t = 150\text{ to } 200\text{ ms}$: Process A executes its remaining $50\text{ ms}$ CPU burst and completes its CPU phase for iteration 1. A immediately moves to I/O for $500\text{ ms}$ (from $t = 200$ to $700\text{ ms}$). Ready Queue: $[\text{B}, \text{C}]$.

• $t = 200\text{ to } 250\text{ ms}$: Process B executes for $50\text{ ms}$ (B has $250\text{ ms}$ remaining). Ready Queue: $[\text{C}, \text{B}]$.

• $t = 250\text{ to } 300\text{ ms}$: Process C executes for $50\text{ ms}$ (C has $100\text{ ms}$ remaining). Ready Queue: $[\text{B}, \text{C}]$.

• $t = 300\text{ to } 350\text{ ms}$: Process B executes for $50\text{ ms}$ (B has $200\text{ ms}$ remaining). Ready Queue: $[\text{C}, \text{B}]$.

• $t = 350\text{ to } 400\text{ ms}$: Process C executes for $50\text{ ms}$ (C has $50\text{ ms}$ remaining). Ready Queue: $[\text{B}, \text{C}]$.

• $t = 400\text{ to } 450\text{ ms}$: Process B executes for $50\text{ ms}$ (B has $150\text{ ms}$ remaining). Ready Queue: $[\text{C}, \text{B}]$.

• $t = 450\text{ to } 500\text{ ms}$: Process C executes its remaining $50\text{ ms}$ CPU burst and completes its CPU execution at $t = 500\text{ ms}$.

At $t = 500\text{ ms}$, Process C initiates its first I/O operation of duration $t_{io} = 500\text{ ms}$.

Therefore, Process C completes its first I/O operation at: