Question

Difficulty: EasySequential Processes and State Transitions

A cloud server processes data batches across three sequential stages (k=1,2,3k = 1, 2, 3). At the start (k=0k = 0), the server has a Buffer size of B0=100 MBB_0 = 100\text{ MB} and a Queue size of Q0=50 MBQ_0 = 50\text{ MB}. In each stage kk, the sizes are updated according to the following rules:
- Bk=Bk120 MBB_k = B_{k-1} - 20\text{ MB}
- Qk=Qk1+10 MBQ_k = Q_{k-1} + 10\text{ MB}

Which of the following statements about the state of the server are true?

  1. At the end of Stage 2 (k=2k = 2), the Buffer size B2B_2 is 60 MB60\text{ MB}.Answer
  2. At the end of Stage 3 (k=3k = 3), the Queue size Q3Q_3 is 80 MB80\text{ MB}.Answer
  3. C
    At the end of Stage 3 (k=3k = 3), the Buffer size B3B_3 is 60 MB60\text{ MB}.
  4. D
    At the end of Stage 2 (k=2k = 2), the Queue size Q2Q_2 is 60 MB60\text{ MB}.
  5. E
    At the end of Stage 1 (k=1k = 1), the combined total volume B1+Q1B_1 + Q_1 is 150 MB150\text{ MB}.

Answer

The correct statements are that at the end of Stage 2, the Buffer size is 60 MB60\text{ MB}, and at the end of Stage 3, the Queue size is 80 MB80\text{ MB}.
The correct statements accurately reflect the iterative evaluation of the state transition formulas: the buffer size decreases by 20 MB20\text{ MB} each stage to reach 60 MB60\text{ MB} at Stage 2, and the queue size increases by 10 MB10\text{ MB} each stage to reach 80 MB80\text{ MB} at Stage 3.

Step-by-Step Solution

1
Calculate state values at Stage 1 (k=1k = 1)
B1=10020=80 MBB_1 = 100 - 20 = 80\text{ MB} and Q1=50+10=60 MBQ_1 = 50 + 10 = 60\text{ MB}. Combined total: 140 MB140\text{ MB}.
Apply the given state transition rules to the initial values at k=0k = 0.
2
Calculate state values at Stage 2 (k=2k = 2)
B2=8020=60 MBB_2 = 80 - 20 = 60\text{ MB} and Q2=60+10=70 MBQ_2 = 60 + 10 = 70\text{ MB}.
Apply the transition rules to the Stage 1 state values.
3
Calculate state values at Stage 3 (k=3k = 3)
B3=6020=40 MBB_3 = 60 - 20 = 40\text{ MB} and Q3=70+10=80 MBQ_3 = 70 + 10 = 80\text{ MB}.
Apply the transition rules to the Stage 2 state values.
4
Evaluate option statements
The statement specifying B2=60 MBB_2 = 60\text{ MB} and the statement specifying Q3=80 MBQ_3 = 80\text{ MB} are verified as correct.
Compare calculated stage states directly against the option statements.

Key Concept

Sequential processes require evaluating every state transition iteratively without skipping intermediate stages.
Rate this question