Use the set of data for questions 4 and 5:
[tex]\[ -3, 11, 4, 12, -1, 0, -3, 17, -4, 1 \][/tex]

4. Find the range and IQR for the data.
5. Find the MAD for the data and determine if there are any outliers.



Answer :

Sure! Let's address each part of the problem in a detailed, step-by-step manner.

### 3. Finding the Range and Interquartile Range (IQR)

Range:
The range of a data set is the difference between the maximum and minimum values.

- Identify the maximum value in the data set: 17
- Identify the minimum value in the data set: -4
- Calculate the range:
[tex]\[ \text{Range} = \text{Maximum} - \text{Minimum} = 17 - (-4) = 17 + 4 = 21 \][/tex]

Thereby, the range of the data is 21.

Interquartile Range (IQR):
The interquartile range is the range between the first quartile (Q1) and the third quartile (Q3).

- First, sort the data:
[tex]\[ -4, -3, -3, -1, 0, 1, 4, 11, 12, 17 \][/tex]
- Find Q1 (the 25th percentile) and Q3 (the 75th percentile):
- Q1 (25th percentile): [tex]\[ Q1 = -1 \][/tex]
- Q3 (75th percentile): [tex]\[ Q3 = 10.75 \][/tex]

- Calculate the IQR:
[tex]\[ \text{IQR} = Q3 - Q1 = 10.75 - (-1) = 10.75 + 1 = 11.75 \][/tex]

So, the interquartile range (IQR) of the data is 11.75.

### 4. Finding the Mean Absolute Deviation (MAD) and Outliers

Mean Absolute Deviation (MAD):
The mean absolute deviation is the average of the absolute deviations from the median of the data set.

- Compute the median of the data set. For data sorted as:
[tex]\[ -4, -3, -3, -1, 0, 1, 4, 11, 12, 17 \][/tex]
The median (the middle value) is the average of the 5th and 6th values:
[tex]\[ \text{Median} = \frac{0 + 1}{2} = \frac{1}{2} = 0.5 \][/tex]

- Calculate the absolute deviations from the median (0.5):
[tex]\[ \left| -4 - 0.5 \right|, \left| -3 - 0.5 \right|, \left| -3 - 0.5 \right|, \left| -1 - 0.5 \right|, \left| 0 - 0.5 \right|, \left| 1 - 0.5 \right|, \left| 4 - 0.5 \right|, \left| 11 - 0.5 \right|, \left| 12 - 0.5 \right|, \left| 17 - 0.5 \right| \][/tex]

These deviations are:
[tex]\[ 4.5, 3.5, 3.5, 1.5, 0.5, 0.5, 3.5, 10.5, 11.5, 16.5 \][/tex]

- Compute the mean of these absolute deviations:
[tex]\[ \text{MAD} = \frac{4.5 + 3.5 + 3.5 + 1.5 + 0.5 + 0.5 + 3.5 + 10.5 + 11.5 + 16.5}{10} = 5.6 \][/tex]

Thus, the mean absolute deviation (MAD) for the data is 5.6.

Outliers:
To determine the outliers, we use the IQR method with a multiplier of 1.5.

- Calculate the lower bound:
[tex]\[ \text{Lower Bound} = Q1 - 1.5 \times \text{IQR} = -1 - 1.5 \times 11.75 = -1 - 17.625 = -18.625 \][/tex]

- Calculate the upper bound:
[tex]\[ \text{Upper Bound} = Q3 + 1.5 \times \text{IQR} = 10.75 + 1.5 \times 11.75 = 10.75 + 17.625 = 28.375 \][/tex]

Any data point outside the range of \([-18.625, 28.375]\) is considered an outlier.

Upon examination, none of the data points fall outside this range, so there are no outliers in the given data set.

### Summary:
- The range of the data is 21.
- The interquartile range (IQR) is 11.75.
- The mean absolute deviation (MAD) is 5.6.
- There are no outliers in the data set.