1. Calculate the reliability of the following system.
.85 .85 .85
.85 .85 .85
2. Karen Perez runs an office supply store that also performs simple office services, such as copying. It is time to purchase a new high-speed copier and Karen has learned that machine uptime is a critical factor in selection. She has gathered the following data on reliability and maintainability for the three copiers she is considering. Given that all other factors are equal, which machine should Karen purchase?
Copier Mean time between failure (hours) Mean time to repair (hours)
Able Copy 40 1
Business Mate 80 4
Copy Whiz 240 8
3. Don't forget the flow chart for this problem. A picture will be attached with this.
During registration at Tech every quarter, students in the Department of Management must have their courses approved by the department advisor. It takes the advisor an average of five minutes (exponentially distributed) to approve each schedule, and students arrive at the advisor's office at the rate of 10 per hour (Poisson distributed). Compute L, Lq, W, Wq, and p. What do you think about this system? How would you change it?
4. Creative Design makes intricate jewelry out of precious metal. The company is introducing a new line and needs to select a manufacturing process. Three options are available. The first involves using a mold to mass produce the design for pendants, earrings, and bracelets. The second option laser cuts the design from a block of metal using a pattern directed by the software. The third option builds the design out of metal powder (gold, silver, and bronze) via a 3D printer. The company is uncertain about demand for the new design.
Option Fixed Cost Variable Cost
1 $10,000 $10
2 $5,000 $30
3 $3,000 $50
a. If Creative Designs expects to sell 200 pieces of the new design, which process should it use?
b. If Creative Designs expects to 1000 pieces of the new design, which process should it use?
c. Create a decision rule that specifies which process to select for different levels of demand.