The demand for an expensive spare part of a passenger jet is 0, 1, 2, or 3

Question:

The demand for an expensive spare part of a passenger jet is 0, 1, 2, or 3 units per month with probabilities .2, .3, .4, and .1, respectively. The airline maintenance shop starts operation with a stock of 5 units and will bring the stock level back to 5 units immediately after it drops below 2 units.

(a) Devise the procedure for sampling demand.

(b) How many months will elapse until the first replenishment occurs? Use the top random numbers in column 1 in Table 19.1.

TABLE 19.1