Home › Previous year questions › GATE 2021 PI › Question 38GATE 2021 PI – Question 38 Quality and Reliability · Reliability and Maintenance · 2 marks · Multiple choice
Identical independent components form a parallel system of reliability 0.97. Each component reliability is 0.68. Find the number of components; round a fractional result upward.
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Show answer and explanation Correct answer: (B) 4
Explanation $R_s=1-(1-R)^n$ gives $0.32^n=0.03$, so $n=\ln0.03/\ln0.32\approx3.08$. Round up to **4, B** to meet or exceed the target.
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