Question
In: Statistics and Probability
A certain survey is conducted by choosing randomly 10 students and asked them about the number...
A certain survey is conducted by choosing randomly 10 students and asked them about the number of hours each of them spent on preparing for a final exam. The following are their answers to the question: 6,11,8,7,4,14,1,10,5,12
a- Construct the boxplot for the time spent studying for the exam.
b- Describe the distribution of the time spent studying for the exam
c- Find a 99% confidence interval for the mean time spent for studying
d- Interpret the confidence interval in (c).
Solutions
Expert Solution
Given:
A certain survey is conducted by choosing randomly 10 students and asked them about the number of hours each of them spent on preparing for a final exam.
The following are their answers to the question: 6,11,8,7,4,14,1,10,5,12 :
Arrange the given data in ascending order
1, 4, 5, 6, 7, 8, 10, 11, 12, 14
Five numbers summary :
Minimum = 1
First quartile, Q1 : first quartile is the median of the first half of the data
Q1 = 5
Median, Q2 = (7+8)/2 = 7.5
Third quartile, Q3 : Third quartile is the median of the second half of the data.
Q3 = 11
Maximum = 14
The boxplot for the time spent studying :
b) Since mean = 7.8 > median = 7.5, the distribution is positively skewed or skewed to right.
d) Interpretation :
We are 99% confident that the mean time spent for studying is between 3.70 and 11.90
orchestra answered 1 year agoRelated Solutions
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