A factory produces light bulbs. A quality control inspector tests a random sample of 250 bulbs and finds that 15 are defective. Estimate the probability that a light bulb chosen at random from the factory's production is defective.

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Question

A factory produces light bulbs. A quality control inspector tests a random sample of 250 bulbs and finds that 15 are defective. Estimate the probability that a light bulb chosen at random from the factory's production is defective.

Accepted Answer

0.06 — 06. Award 1 mark for calculating 15 ÷ 250 = 0.06. B is incorrect — uses the number of defective bulbs rather than the ratio. C is incorrect — calculates the probability of a non-defective bulb (235 ÷ 250). D is incorrect — incorrectly inverts the calculation (250 ÷ 15).

Answer

0.94

Answer

0.15

Answer

16.67

Answer

0.06

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