SOLUTION: The lifetimes of lightbulbs of a particular type are normally distributed with a mean of 370 hours and a standard deviation of 10 hours. What percentage of the bulbs have lifetimes

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Question 1157169: The lifetimes of lightbulbs of a particular type are normally distributed with a mean of 370 hours and a standard deviation of 10 hours. What percentage of the bulbs have lifetimes that lie within 1 standard deviation to either side of the mean?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The estimate between -1 and +1 is 68% (95% for 2 sd s, 99.7% for 3)
it is 68.27%