To analyze the statements based on the provided dot plots for teachers and students, we should first determine the relevant statistics: the maximum, mean, range, and median number of siblings.
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Maximum number of siblings:
- Teachers: The maximum from the dot plot is 9 (with 1 closed circle).
- Students: The maximum from the dot plot is 7 (with 1 closed circle).
So, the maximum number of siblings for students is not greater than that for teachers.
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Mean number of siblings:
- Teachers:
- Calculation:
- (0×3 + 1×3 + 2×4 + 3×3 + 4×2 + 5×3 + 6×1 + 9×1) / 20
- = (0 + 3 + 8 + 9 + 8 + 15 + 6 + 9) / 20
- = 58 / 20 = 2.9
- Calculation:
- Students:
- Calculation:
- (0×1 + 1×2 + 2×4 + 3×5 + 4×4 + 5×1 + 6×2 + 7×1) / 20
- = (0 + 2 + 8 + 15 + 16 + 5 + 12 + 7) / 20
- = 65 / 20 = 3.25
- Calculation:
Thus, the mean number of siblings for teachers (2.9) is not higher than that for students (3.25).
- Teachers:
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Range of siblings:
- Teachers: Maximum is 9, minimum is 0; range = 9 - 0 = 9.
- Students: Maximum is 7, minimum is 0; range = 7 - 0 = 7.
Therefore, the range of the number of siblings for teachers (9) is indeed higher than that of the students (7).
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Median number of siblings:
- Teachers: When sorted, the number of siblings will be:
- 0 (3), 1 (3), 2 (4), 3 (3), 4 (2), 5 (3), 6 (1), 9 (1)
- This results in: 0, 0, 0, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 5, 5, 5, 6, 9
- The median (10th and 11th values) = (2+3)/2 = 2.5.
- Students: When sorted, the number of siblings will be:
- 0 (1), 1 (2), 2 (4), 3 (5), 4 (4), 5 (1), 6 (2), 7 (1)
- This results in: 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 5, 6, 6, 7
- The median = (3+3)/2 = 3.
Hence, the median number of siblings for students (3) is indeed higher than that for teachers (2.5).
- Teachers: When sorted, the number of siblings will be:
Based on this analysis, the correct statement is:
The median number of siblings for students is higher than the median number of siblings for teachers.