Using the Empirical Rule, it is found that:
a) 68% of the widget weights lie between 35 and 57.
b) The percentage is 81.5%.
c) The percentage is 99.85%.
What does the Empirical Rule state?
It states that, for a normally distributed random variable:
- Approximately 68% of the measures are within 1 standard deviation of the mean.
- Approximately 95% of the measures are within 2 standard deviations of the mean.
- Approximately 99.7% of the measures are within 3 standard deviations of the mean.
For this problem, we have that:
- In item a, 68% of the widgets are within 1 standard deviation of the mean, hence between 35 and 57.
- In item b, between 2 standard deviations below the mean(95% of 50% due to the symmetry of the normal distribution) and 1 above(68% of 50%), hence the percentage is: P 34% + 47.5% = 81.5%.
- For item 3, below 3 standard deviations above the mean, hence removes only the top 0.15%, hence 99.85%.
More can be learned about the Empirical Rule at https://brainly.com/question/4079902
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