I came across this problem during a GMAT Prep exam. No explanations provided, only the correct answer. Please explain how you arrived at the answer. Thanks.
The distribution of the results of a survey had a mean of 21 hours and a standard deviation of 6 hours. The # of hours that Pat watched TV last week was between 1 and 2 standard deviation below the mean. Which of the following could be the # of hours Pat spent watching TV?
a) 30
b) 20
c) 18
d) 12
e) 6
D is correct answer.
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Standard Deviation Problem on GMAT Prep
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outreach
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selango
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Mean=21
SD=6
1 SD below the mean=21-6=15
2 SD below the mean=21-12=9
between 9 and 15
12 only satisfy the above.
Hence D
For SD and Mean prob like this you can use the below formula,
SD=6
1 SD below the mean=21-6=15
2 SD below the mean=21-12=9
between 9 and 15
12 only satisfy the above.
Hence D
For SD and Mean prob like this you can use the below formula,
--Anand--
