Judy Jones Purchases Groceries and Pop Exactly Once Each Week

Multiple Choice

Judy Jones purchases groceries and pop exactly once each week on Sunday evenings. She buys either Coke or Pepsi only and switches from Coke to Pepsi and vice-versa somewhat regularly. Her purchasing behavior of these two drinks is modeled as a Markov system. Let the transition matrix be:

In the next 700 weeks, on an average, how many weeks is Judy expected to purchase Pepsi?

A) 400
B) 420
C) 300
D) 210