SOLUTION: The ages in the data set can be shown to be approximately normally distributed with a mean of 50 years and a standard deviation of 6 years. A person is randomly selected and their

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Question 628513: The ages in the data set can be shown to be approximately normally distributed with a mean of 50 years and a standard deviation of 6 years. A person is randomly selected and their age observed. Find the probability that their age will fall between 55 and 60.
Now I got some of it: Z = (55-50/6) = (5/6) = 0.8333 = 0.2967 My question is where does 0.2967 come from?
How is that calculated from Z = (55-50/6) = (5/6) = 0.8333?
Please tell me how to enter it in my calculator. Thank you in advance.
Answer by John10(297) (Show Source):
You can put this solution on YOUR website!
The ages in the data set can be shown to be approximately normally distributed with a mean of 50 years and a standard deviation of 6 years. A person is randomly selected and their age observed. Find the probability that their age will fall between 55 and 60.
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Find z-score of x = 55 and z = 60
z(55) = (55 - 50)/6 = 5/5 = 0.833
z(60) = (60 - 50)/6 = 10/6 = 1.67
Now we find the probability between 55 and 60:
P(55 < x < 60) = (0.83 < z < 1.67) = 0.156
Calculator: If you have TI-83 plus, you will press 2nd VARS the press "2" you will see "normalcdf(0.83, 1.67)".
Hope it helps:)
John10:)