Asked by Nguyen Danny on Jun 13, 2024

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The test scores of 19 students are listed below.Find the upper quartile (Q3) by hand. 36 45 49 53 55
56 59 61 62 65
67 71 75 79 82
88 90 92 97

A) 55.5
B) 82.0
C) 65.0
D) 79.0
E) 80.5

Upper Quartile

The value below which 75% of the data set falls, marking the upper quarter of data points.

Test Scores

Numerical or grading assessments that reflect the performance of individuals on examinations or tests.

  • Ascertain quartiles and implement quartile computations on practical data sets.
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RM
Roxanna MarieJun 17, 2024
Final Answer :
B
Explanation :
To find the upper quartile, we need to first find the median (Q2) of the data set.
The median is the middle value, so we need to find the average of the two middle values since we have an odd number of data points.
Median (Q2) = (65+67)/2 = 66
Next, we need to find the median of the upper half of the data set.
There are 9 data points to the right of the median, so we need to find the average of the two middle values in that set.
The upper half of the data set is:
67 71 75 79 82 88 90 92 97
Median of Upper Half (Q3) = (82+88)/2 = 85
Therefore, the upper quartile (Q3) is 85. Answer choice B is correct.