A certain market has both an express checkout line and a super-express checkout

Question

A certain market has both an express checkout line and a super-express checkout line. Let X1 denote the number of customers in line at the express checkout at a particular time of day, and let X2 denote the number of customers in line at the superexpress checkout at the same time. Suppose the joint pmf of X1 and X2 is as given in the accompanying table.

x2

The difference between the number of customers in line at the express checkout and the number in line at the superexpress checkout is X1 X2. Calculate the expected difference.

A certain market has both an express checkout line and a super-express checkout line. Let X1 denote the number of customers in line at the express checkout at a particular time of day, and let X2 denote the number of customers in line at the superexpress checkout at the same time. Suppose the joint pmf of X1 and X2 is as given in the accompanying table.

x2

  0     1     2     3   x1   0   0.08 0.09 0.04 0.00   1   0.04 0.16 0.05 0.03   2   0.05 0.04 0.10 0.06   3   0.00 0.03 0.04 0.07   4   0.00 0.01 0.05 0.06

Explanation / Answer

here joint pmf of X1,X2 is as follows:

marginal pmf of X1:

and marginal pmf od X2:

hence  expected difference. =E(X1)-E(X2) =1.68-1.55 =0.13

please revert for any clarification required,

x2 x1 0 1 2 3 Total 0 0.0800 0.0900 0.0400 0.0000 0.2100 1 0.0400 0.1600 0.0500 0.0300 0.2800 2 0.0500 0.0400 0.1000 0.0600 0.2500 3 0.0000 0.0300 0.0400 0.0700 0.1400 4 0.0000 0.0100 0.0500 0.0600 0.1200 Total 0.1700 0.3300 0.2800 0.2200 1.0000

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.