SOLUTION: This is for Biostatistics Among coffee drinkers, men drink a mean of 3.2 cuops per day with a standard deviaiton of 0.8 cups. Assume thenumber of cups per day follows a norma

Question 226584: This is for Biostatistics
Among coffee drinkers, men drink a mean of 3.2 cuops per day with a standard deviaiton of 0.8 cups. Assume thenumber of cups per day follows a normal distribution.:
A) What proportion drink 2 cups per day or more?
b) what proportion drink no more than 4 cups per day?
c) If the top 5% if ciffee drinkers are considered "heavy" coffee drinkers, what is the minium number of cups consumed by a heavy coffee drinker?
I need the formulas?
Answer by scott8148(6628) (Show Source): You can put this solution on YOUR website!
this is all in a z-score table

A) 2 is 1.2 below 3.2 ___ -1.2/.8 = -1.5 ___ this is the z-score
using the table ___ 5.6% are BELOW 2 cups per day, so 94.4% drink at least 2 cups per day

B) 4 is .8 above 3.2 so the z-score is 1
using the table ___ 84.1% drink no more than 4 cups per day

C) using the table ___ the top 5% have a z-score of 1.645 or above
.8 * 1.645 = 1.32 ___ 3.2 + 1.32 = 4.52
so the top 5% drink at least 4.52 cups per day
RELATED QUESTIONS
1. Among cofee drinkers, men drink of 3.2 cups per day with a standard deviation of 0.8... (answered by stanbon)

Among Coffee drinkers, men drink a mean of 3.2 cups per day, with a standard deviation of (answered by rothauserc)

Among coffee drinkers, men drink a mean of 3.2 cups per day with a standard deviation of... (answered by Boreal)

My question:Among coffee drinkers, men drank a mean of 3.2 cups per day with a standard... (answered by ewatrrr)

The amount of coffee that people drink per day is normally distributed with a mean of 17... (answered by Boreal)

Trying to find the answer for this: A coffee manufacturer is interested in whether the (answered by rothauserc)

A coffee manufacturer is interested in whether the mean daily consumption of... (answered by Boreal)

A national survey of graduate students is conducted to assess their consumption of coffee (answered by ewatrrr)

Problem 4, the following data were collected as part of a study of coffee consumption... (answered by stanbon)