1. **State the problem:** We need to create a box-and-whisker plot for the data set: 15, 21, 16, 15, 14, 8, 16, 15, 15, 17, 18, 14. 2. **Organize the data:** Sort the data in ascending order: $$8, 14, 14, 15, 15, 15, 15, 16, 16, 17, 18, 21$$ 3. **Find the minimum and maximum values:** - Minimum = 8 - Maximum = 21 4. **Find the median (Q2):** Since there are 12 data points (even number), median is the average of the 6th and 7th values: $$\text{Median} = \frac{15 + 15}{2} = 15$$ 5. **Find the first quartile (Q1):** Q1 is the median of the lower half (first 6 values): 8, 14, 14, 15, 15, 15 Median of these is average of 3rd and 4th values: $$Q1 = \frac{14 + 15}{2} = 14.5$$ 6. **Find the third quartile (Q3):** Q3 is the median of the upper half (last 6 values): 15, 16, 16, 17, 18, 21 Median is average of 3rd and 4th values: $$Q3 = \frac{16 + 17}{2} = 16.5$$ 7. **Summary statistics:** - Minimum = 8 - Q1 = 14.5 - Median = 15 - Q3 = 16.5 - Maximum = 21 8. **Interpretation:** The box spans from Q1 to Q3 (14.5 to 16.5), with a line at the median (15). Whiskers extend from minimum (8) to maximum (21). Final answer: The box-and-whisker plot is based on these five-number summary values.