Determine the probability of each number of planes soldof 0, 1, 2, 3in a 50-week period. (Pioneer sales office is closed the other two weeks of the year.)

Pioneer Aircraft Co. sells private, single-engine planes. Most sales are for customers engaged in private and leisure flying. In a 50-week period, sales in the past five years have averaged to the following:
PLANES SOLD WEEKS THIS NUMBER SOLD
0 40
1 8
2 1
3 1
In a three-page essay, determine the items below:
Determine the probability of each number of planes soldof 0, 1, 2, 3in a 50-week period. (Pioneer sales office is closed the other two weeks of the year.)
Decide what approach is best used to determine probability. Distinguish between the approaches to make it clear that the approach used was the best fit for these airplane sales.
Determine if the approach would change if we also needed to track sales of some planes with GPS installed.