To determine which statements are correct, we need to analyze the given data set:
23, 45, 39, 57, 31, 53, 28, 50, 42, 36
First, we should sort the data:
Sorted data: 23, 28, 31, 36, 39, 42, 45, 50, 53, 57
Next, we can find the quartiles and median:
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Median:
- The median is the average of the 5th and 6th values (since there are 10 values, the median will be the average of the 5th and 6th values).
- 5th value: 39
- 6th value: 42
- Median = (39 + 42) / 2 = 40.5
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Lower Quartile (Q1):
- The lower quartile is the median of the first half of the data (23, 28, 31, 36, 39).
- 3rd value (the median of the first half): 31 (as it is the 3rd of 5 values).
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Upper Quartile (Q3):
- The upper quartile is the median of the second half of the data (42, 45, 50, 53, 57).
- 3rd value of the second half: 50.
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Interquartile Range (IQR):
- IQR = Q3 - Q1
- IQR = 50 - 31 = 19.
Now, let's check each of the statements:
- The upper quartile is 50. (Correct)
- The lower quartile is 31. (Correct)
- The interquartile range is 19. (Correct)
- The lower quartile is 36. (Incorrect, it is 31)
- The upper quartile is 53. (Incorrect, it is 50)
- The median is 40.5. (Correct)
- The median is 41. (Incorrect, it is 40.5)
Thus, the four correct statements are:
- The upper quartile is 50.
- The lower quartile is 31.
- The interquartile range is 19.
- The median is 40.5.