Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

A recording company obtains the blank CDs used to produce its labels from three

ID: 3084316 • Letter: A

Question

A recording company obtains the blank CDs used to produce its labels from three compact disk manufacturers: I, II, and III. The quality control department of the company has determined that 3% of the compact disks produced by manufacturer I are defective, 5% of those produced by manufacturer II are defective, and 5% of those produced by manufacturer III are defective. Manufacturers I, II, and III supply 36%, 54%, and 10%, respectively, of the compact disks used by the company. What is the probability that a randomly selected label produced by the company will contain a defective compact disk?

Explanation / Answer

Manufacturer -CDs supplied(%) --Defective CDS (%) in the total discs

              1 -    36            - 3% of 36 = 1.08

2 -    54    - 5% of 54 = 2.7

             3 -           10            - 5% of 10 = 0.5

Total discs supplied = 100%

Total defective discs = 1.08+2.7+0.5 = 4.28%

Probability of defective disc suppilied = 4.28/100 =0.0428