OPRE 6302 on 20 March 2008 - The University of Texas at Dallas

(a) 12 hours 47 minutes
(b) 15 hours
(c) Less than 10 hours
(d) 55 hours
(e) Between 45 and 50 hours
A, 22+5*149=767 mins, Larissa
6. All hand-carry bags have to be X-rayed at airports. X-ray machines have conveyer belts transferring bags
to and through the X-ray machine. The portion of the belt outside the machine usually holds 4 bags at a
given time and it takes 12 seconds for a bag to reach the machine. Then an X-ray inspector looks at the
X-ray picture of the bag while it is on the belt but inside the X-Ray machine. Checking the picture takes
3 seconds per bag. Which of the following is the capacity in bags/minute of the entire X-raying operation
including bag transfers?
(a) 10
(b) 15
(c) 20
(d) 25
(e) None of the above
A, 10 per minute, six seconds for each bag. 3 sec in the machine. 3 seconds to the machine. Yi-Fan
7. Computers R Us has COGS of $18 B per year and keeps $450 M of inventory, what is the flowtime of an
average item in days (A month has 30 days, a year has 12 months)?
(a) 10
(b) 15
(c) 20
(d) 25
(e) None of the above
E 0.45/180=1/40 year=12/40 months=3/10 months=9 days. Liz Reeves
8. Which of the following is not a reason why companies plan to hold inventory?
(a) Due to pipeline inventory
(b) Unstable demand and supply
(c) Economies of scale
(d) To have buffers so disruption of an activity does not stop the whole process
(e) To accommodate the excess supply which exceeds the demand
E June Lee
9. In an assembly operation at a furniture factory, five workers assemble an average of 350 standard dining
chairs per 7-day week. What is the labor productivity of this operation?
(a) 50 chairs/(worker x week)
(b) 70 chairs/week
(c) 10 chairs/(worker x week)
(d) 50 chairs/day
(e) 70 chairs/(worker x day)