1. **Problem statement:** Given detection times: 12, 14, 13, 15, 13, 16, 14, 13, 17, 12, we need to compute various statistics.
2. **Sum of all detection times:**
$$\text{Sum} = 12 + 14 + 13 + 15 + 13 + 16 + 14 + 13 + 17 + 12 = 139$$
3. **Mean (exact):**
$$\text{Mean} = \frac{\text{Sum}}{n} = \frac{139}{10} = 13.9$$
4. **Mean rounded to two decimals:**
$$13.90$$
5. **Ordered data (ascending):**
$$12, 12, 13, 13, 13, 14, 14, 15, 16, 17$$
6. **5th value in ordered data:**
$$13$$
7. **6th value in ordered data:**
$$14$$
8. **Median detection time:**
Since $n=10$ (even), median is average of 5th and 6th values:
$$\text{Median} = \frac{13 + 14}{2} = 13.5$$
9. **Mode of detection times:**
The value appearing most frequently is $13$ (appears 3 times).
10. **Sum of absolute deviations about the mean:**
Calculate each absolute deviation:
$|12-13.9|=1.9$, $|14-13.9|=0.1$, $|13-13.9|=0.9$, $|15-13.9|=1.1$, $|13-13.9|=0.9$, $|16-13.9|=2.1$, $|14-13.9|=0.1$, $|13-13.9|=0.9$, $|17-13.9|=3.1$, $|12-13.9|=1.9$
Sum:
$$1.9 + 0.1 + 0.9 + 1.1 + 0.9 + 2.1 + 0.1 + 0.9 + 3.1 + 1.9 = 13.0$$
11. **Mean absolute deviation (MAD):**
$$\text{MAD} = \frac{13.0}{10} = 1.30$$
12. **Median absolute deviation (MeD):**
Order absolute deviations:
$$0.1, 0.1, 0.9, 0.9, 0.9, 1.1, 1.9, 1.9, 2.1, 3.1$$
Median is average of 5th and 6th:
$$\frac{0.9 + 1.1}{2} = 1.00$$
13. **Skewness:**
Since mean (13.9) > median (13.5) > mode (13), the distribution is positively skewed (right-skewed).
**Final answers:**
(a) 139
(b) 13.9
(c) 13.90
(d) 13
(e) 14
(f) 13.5
(g) 13
(i) 13.00
(j) 1.30 (MAD), 1.00 (MeD)
(k) Positively skewed because mean > median > mode.
Detection Times Bf8972
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