Standard Deviation: A coffee machine is regulated so that the amount delivered per...

vinnyd53

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** Hi there, I'm having difficulty with a question from some schools past exam papers, one of the question is about standard deviation which i'm not great at the question goes like this**


A coffee machine is regulated so that the amount delivered per cup is normally distributed with a mean of 210ml and a standard deviation of 4ml

(a) What percentage of cups will contain:
(i) less than 203ml?
(ii) more than 212ml?
(iii) between 213.75ml and 219.46ml?

**Then the last question confuses me greatly My English isn't great and I dont understand where they are getting all these crazy figures from, like how can you possibly have less than 203ml if the mean is 210ml and deviation is 4ml wouldn't the lowest possible amount be 206ml? I'm just confused and I'm teaching my self which isnt the best idea so I came here for guidance, heres the last question**


(b) Below what amount does the bottom 7%(?) of the distribution lie?

**sorry for the long post and thank you for reading**
 
** Hi there, I'm having difficulty with a question from some schools past exam papers, one of the question is about standard deviation which i'm not great at the question goes like this**


A coffee machine is regulated so that the amount delivered per cup is normally distributed with a mean of 210ml and a standard deviation of 4ml

(a) What percentage of cups will contain:
(i) less than 203ml?
(ii) more than 212ml?
(iii) between 213.75ml and 219.46ml?

**Then the last question confuses me greatly My English isn't great and I dont understand where they are getting all these crazy figures from, like how can you possibly have less than 203ml if the mean is 210ml and deviation is 4ml wouldn't the lowest possible amount be 206ml? I'm just confused and I'm teaching my self which isnt the best idea so I came here for guidance, heres the last question**


(b) Below what amount does the bottom 7%(?) of the distribution lie?

**sorry for the long post and thank you for reading**


Study Normal z-distribution/transformation.
 
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