One of the industrial robots designed by a leading producer of servomechanisms has four major components. Components reliabilities are .98, .95, .94, and .90. All of the components must function in order for the robot to operate effectively.
a. Compute the reliability of the robot.
b. Designers want to improve the reliability by adding a backup component. Due to space limitations, only one backup can be added. The backup for any component will have the same reliability as the unit for which it is the backup. Which component should get the backup in order to achieve the highest reliability?
c. If one backup with a reliability of .92 can be added to any one of the main components, which component should get it to obtain the highest overall reliability?