1/2

İstanbul Kültür University

Faculty of Engineering and Architecture Department of Industrial Engineering

IE 250 Introduction to Industrial Engineering – Final Exam Practice

Question 1 (20 points) Determine the critical path for the network shown below, where the numbers are to – tm – tp. What is the time of completion for the critical path that has an 80% chance of being achieved?

Question 2 (15 points) You invest $1000 at the end of each year for 10 years (beginning with end of year 1) and then stop adding to the investment. Your fiend then starts investing $1000 at the end of each year (beginning with the end of year 11) forever. Both investments earn 12%. In what year will your friend’s investment be worth more than yours?

2/2

Question 3 (15 points) If a new machine is available that costs $60,000 and will last 5 years, at which time it can be sold at $20,000, how much would that machine have to save each year in order for the purchase of it to be economically advisable? The annual interest rate is 10%. Question 5 (15 points)

Annual usage of an item is 1000 units. Ordering cost is $10 per order, and carrying cost is $0.50 per unit per year. Determine the optimal order quantity for this item. How many orders will be placed during the year? How many days will there be between consecutive orders? Show all you computed on the inventory geometry (Assume 250 working days in a year).