Body Temperatures: Most people think that the \"normal\" adult body temperature
ID: 3130733 • Letter: B
Question
Body Temperatures: Most people think that the "normal" adult body temperature is 98.6 degrees Fahrenheit. That figure, based on a 19th century study, has recently been challenged. A more recent Figure is 98.3 degrees. The standard deviation appears to be around 0.7 degrees and the distribution is approximately Normal. A) Based on this model, below what body temperature are the coolest 20% of all people? degrees (Round your answer to 1 decimal place) B) Based on this model, above what body temperature are the hottest 10% of all people? degrees (Round your answer to 1 decimal place)Explanation / Answer
A)
First, we get the z score from the given left tailed area. As
Left tailed area = 0.2
Then, using table or technology,
z = -0.841621234
As x = u + z * s,
where
u = mean = 98.3
z = the critical z score = -0.841621234
s = standard deviation = 0.7
Then
x = critical value = 97.71086514 [ANSWER]
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b)
First, we get the z score from the given left tailed area. As
Left tailed area = 1 - 0.10 = 0.9
Then, using table or technology,
z = 1.281551566
As x = u + z * s,
where
u = mean = 98.3
z = the critical z score = 1.281551566
s = standard deviation = 0.7
Then
x = critical value = 99.1970861 [ANSWER]