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#1




Another question about Normal Gaussian Distribution
The purpose of a study by Luglie et al was to investigate the oral status of a group of patients diagnosed with thalassemia major (TM). One of the outcome measures was the decayed, missing, and filled teeth index (DMFT). In a sample of 100 patients, the mean DMFT index value was 18 with a standard error of 1.2.
What percentage of people will be in the interval [6, 42]? a) 50% b) 68.2% c) 81.8% d) 99.7% e) more information is need it 
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#2




SE=SD/square root of n
so SD=SE x square of n =1.2x10(squareroot of 100) SD=12 As mean is 18 ,so 6 will be 1 SD below the mean and 42 will be 2SD above the mean 1SD above and below the mean is equal to 68% and as 42 is 2SD above the mean we will add 13.2% So ,answer will be 81.3% in simple words,34+34+13=81% 
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#3




Quote:

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#4




Answer should be c, explained accurately by struggle 81%

#5




YES, the correct answer is indeed C).
point to remember: SD is not the same as SE 
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BiostatisticsEpidemiology, Step1Questions 
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