A hardware manufacturer produces nuts and bolts. Each bolt produced is attached to a nut to make a single unit. It is known that 2% of the nuts produced and 3% of the bolts produced are defective in some way. A nut-bolt unit is considered defective if either the nut or the bolt has a defect.
a. Determine the percentage of defective nut-bolt units.
b. What assumptions are you making in solving part (a)?