Confused

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Confused
Message posted by Mandy on November 16, 2000 at 12:00 AM (ET)

I have a problem that is giving me fits. I know I can use the Norminv function in Excel to solve part b, but I do notknow how to solve part a. Any help would be appreciated.

To be eligible for the U.S. Marine Corps, a woman must have a height between 58 inches and 73 inches. Women have normally distributed heights with a mean of 63.6 inches and a standard deviation of 2.5 inches.
a) Find the percentage of women who satisfy the Marine Corps height requirement.

b)If the requirement is changed to exclude the shortest 1% and the tallest 1% of all women, find the heights that are acceptable

READERS RESPOND:
(In chronological order. Most recent at the bottom.)

Re: Confused
Message posted by JG on November 16, 2000 at 12:00 AM (ET)

a) 98.7%

b) 57.8 to 69.4 inches

Re: Confused
Message posted by Mandy on November 16, 2000 at 12:00 AM (ET)

How did you come up with the 98.7% in part A?

Re: Confused
Message posted by JG on November 17, 2000 at 12:00 AM (ET)

P(Z LE -2.24) = .o13 and
-2.24=(58-63.6)/2.5 . See a basic statistics book for further details.

Re: Confused
Message posted by Many on November 17, 2000 at 12:00 AM (ET)

I still don't understand how you get the 98.7%. What do the letters stand for? We weren't taught to use these in our class.

Thanks once again.

Re: Confused
Message posted by Mandy on November 17, 2000 at 12:00 AM (ET)

Never mind. I figured it help and thanks for your help once again.

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