5.2-10 – Introductory Statistics – Sheldon M. Ross

Question:

A contractor will bid for two jobs in sequence. She has a 0.5 probability of winning the first job. If she wins the first job, then she has a 0.2 chance of winning the second job; if she loses the first job, then she has a 0.4 chance of winning the second job. (In the latter case, her bid will be lower.) Let X denote the number of jobs that she wins. Find the probability distribution of X.

Solution:

Let X = the number of jobs that are won

X	P (X)
0	0.1
1	0.6
2	0.3
	1.0