Ask Question
25 October, 11:41

The amount of time a certain brand of light bulb lasts is normally distribued with a mean of 1400 hours and a standard deviation of 55 hours. Using the empirical rule, what percentage of light bulbs last between 1345 hours and 1455 hours?

+1
Answers (1)
  1. 25 October, 13:01
    0
    By the Empirical Rule, 68% of light bulbs last between 1345 hours and 1455 hours

    Step-by-step explanation:

    The Empirical Rule states that, for a normally distributed random variable:

    68% of the measures are within 1 standard deviation of the mean.

    95% of the measures are within 2 standard deviation of the mean.

    99.7% of the measures are within 3 standard deviations of the mean.

    In this problem, we have that:

    Mean = 1400 hours

    Standard deviation = 55 hours

    Using the empirical rule, what percentage of light bulbs last between 1345 hours and 1455 hours?

    1345 = 1400 - 1*55

    So 1345 is one standard deviation below the mean.

    1455 = 1400 + 1*55

    So 1455 is one standard deviation above the mean.

    By the Empirical Rule, 68% of light bulbs last between 1345 hours and 1455 hours
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “The amount of time a certain brand of light bulb lasts is normally distribued with a mean of 1400 hours and a standard deviation of 55 ...” in 📘 Mathematics if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers