Asked by mj
The diameter of an electric cable is normally distributed, with a mean of 0.8 inch and a standard deviation of 0.01 inch. What is the probability that the diameter will exceed 0.81 inch
Answers
Answered by
MathMate
0.81 inch is exactly one standard deviation (s.d.) above the mean of 0.80.
Assuming a normal distribution, you can look up tables, such as:
http://www.math.unb.ca/~knight/utility/NormTble.htm
to find that the probability of not exceeding 1 s.d. above the mean is 0.8413.
Therefore the probability of <i>exceeding</i> 1 s.d. is 1-0.8413.
Assuming a normal distribution, you can look up tables, such as:
http://www.math.unb.ca/~knight/utility/NormTble.htm
to find that the probability of not exceeding 1 s.d. above the mean is 0.8413.
Therefore the probability of <i>exceeding</i> 1 s.d. is 1-0.8413.