1. **Stating the problem:** Calculate the median, mode (dominanta), and arithmetic mean (średnia arytmetyczna) for the data set: $$7, 4, 3, 8, 3, 4, 3$$ 2. **Order the data:** $$3, 3, 3, 4, 4, 7, 8$$ 3. **Median:** The median is the middle value in an ordered data set. Since there are 7 values (odd number), the median is the 4th value: $$\text{median} = 4$$ 4. **Mode (dominanta):** The mode is the value that appears most frequently. Here, 3 appears 3 times, more than any other number: $$\text{dominanta} = 3$$ 5. **Arithmetic mean (średnia arytmetyczna):** The mean is the sum of all values divided by the number of values: $$\bar{x} = \frac{7 + 4 + 3 + 8 + 3 + 4 + 3}{7}$$ Calculate the sum: $$7 + 4 + 3 + 8 + 3 + 4 + 3 = 32$$ So: $$\bar{x} = \frac{32}{7}$$ Show cancellation step: $$\bar{x} = \frac{\cancel{32}}{\cancel{7}}$$ Simplify to decimal: $$\bar{x} \approx 4.57$$ **Final answers:** - Median = 4 - Dominanta = 3 - Średnia arytmetyczna $\bar{x} \approx 4.57$