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Statistics for Data Science II · Quiz 2 · 16 Aug 2026 · May 2026 term

Question 10: A factory produces light bulbs. The lifetime of an indiv…

Question 10

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A factory produces light bulbs. The lifetime of an individual bulb has a mean of 1200 hours and a standard deviation of 180 hours. By using Central limit theorem, a quality engineer computes the probability that the average lifetime of a random sample of bulbs is greater than 1230 hours to be approximately 0.07. What is the minimum sample size taken by the engineer ? Solution: Let represents lifetime of an individual bulb with mean =1200 and standard deviation =180. Let be the average lifetime of samples. Therefore, and are and respectively. We are given that, By using CLT, On comparing with Z-values, Consider the following options for the blanks.

Answer the given sub-questions. Note: Enter only the correct option number (e.g. 8) without any brackets or punctuation.

A factory produces light bulbs. The lifetime of an individual bulb has a mean of 1200 hours and a standard deviation of

Calculate the value for .

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Question 10 of 26 in the IIT Madras BS Statistics for Data Science II (Stats 2) Quiz 2 paper sat on 16 Aug 2026, in the May 2026 term (Statistics2 14 Aug 26). It carries 1 mark.

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