Bunuel
An assembly line produces car seats. 18% of the car seats produced by the factory are defective. 95% of the defective car seats were spotted during a routine quality check but 1% of the non-defective seats were also rejected by mistake. Approximately what percentage of the car seats cleared by the assembly line is defective?
(A) 1.1%
(B) 4.5%
(C) 5.7%
(D) 6.2%
(E) 10%
100x Total,
Total Defective = 18% = 18x
Non defective = 82x
Spotted Defective 95% means 5% are mistakenly there non defective carseats. \(= 0.05*18x = 0.9x\)
Plus, 1% of non defective mistakenly rejected \(= 1% of 82x = 0.82x \)
Total of actual non defectives \(= 82x-0.82x = 81.18x\)
Total of non defectives considering mistakenly selected defective \(= 81.18x + 0.9x = 82.08x\)
percentage of the car seats cleared by the assembly line is defective = \(\frac{0.9x}{82.08x} * 100 = 1.096%\)
Answer is A.