SOLUTION: The length of time in hours before a mobile requires charging has a normal distribution with a mean of
100 hours and a standard deviation of 15 hours.
a) Find the probability tha
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-> SOLUTION: The length of time in hours before a mobile requires charging has a normal distribution with a mean of
100 hours and a standard deviation of 15 hours.
a) Find the probability tha
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Question 1182184: The length of time in hours before a mobile requires charging has a normal distribution with a mean of
100 hours and a standard deviation of 15 hours.
a) Find the probability that the time before charging is greater than 127 hours.
b) Find the 10th percentile
c) You are about to go on a 6 hour trip. Given you last charged your phone 127 hours ago, what is
the probability your mobile will not need charging until you complete the trip? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! z=(x-mean)/sd
z>27/15=1.8 and that probability is 0.0359
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10th percentile for z is -1.282
-1.282=(x-mean)/15
-19.22=x-mean (didn't round z until here)
x=80.78 hours
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Essentially want the probability of the mobile phone's going 133 hours without charging, and that is z>33/15 or z>2.2
this probability is 0.0139
