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In: Statistics and Probability

General electric claims that the mean life of their new LED bulb is 2400 hours. Assume...

  1. General electric claims that the mean life of their new LED bulb is 2400 hours. Assume the standard deviation is 240 hours. A consumer agency decides to randomly select 36 bulbs and determine the mean life of the products in the sample. If the manufacturer’s claim is true, what is the probability that
    1. the sample mean is between 2370 and 2430 hours?
    2. The mean of the sample is greater than 2440 hours?
    3. If the agency decides to reject the manufacturer’s claim if the mean of the sample is less than 2330 hours, what is the probability that the claim will be rejected?

Solutions

Expert Solution

Answer a) 0.5467

The probability that the mean of the sample mean is between 2370 and 2430 hours 0.5467

Answer b) 0.1587

The probability that the mean of the sample is greater than 2440 hours is 0.1587

Answer c) 0.0401

The probability that the claim will be rejected is 0.0401

orchestra answered 1 year ago
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