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You are not logged in. #1 20130504 00:15:49
need some help plzbirth weight in US are normally distributed with mean of 340g and a strandard deviation of 45g. If a hospital plans to set up observation condition for the lightest 7% of the babies, what weight is used for the cutoff separating the lightest 7% from the others? #2 20130504 00:22:10
Re: need some help plzHi aric The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #3 20130504 03:41:25
Re: need some help plz
What is the zscore for "7%"? #4 20130504 03:54:43
Re: need some help plzHi aric #6 20130504 17:18:57
Re: need some help plzhi aric, where mu is the mean (340) sigma is the sd (45) and phi is the function that converts this into a probability. Use this page: http://www.mathsisfun.com/data/standard … table.html This interactive graph shows the probabilities as percentages in three possible ways. Click the 'up to z' button to get the 7% area you want. There is a more accurate table of values below the graph. Once you have z, you can solve for x Bob You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei 