1. **Stating the problem:** We have a row of 3 squares made using 10 toothpicks. We need to find how many toothpicks are needed to make a row of 11 squares. 2. **Understanding the pattern:** - Each square has 4 sides. - When squares are placed in a row, they share sides with adjacent squares. - For 3 squares, the total toothpicks used is 10. 3. **Finding the formula:** - For 1 square, toothpicks needed = 4. - For 2 squares, toothpicks needed = 4 + 3 = 7 (since they share one side). - For 3 squares, toothpicks needed = 4 + 3 + 3 = 10. This shows the pattern: toothpicks needed = 4 + 3(n - 1) where $n$ is the number of squares. 4. **Calculating for 11 squares:** $$\text{toothpicks} = 4 + 3(11 - 1) = 4 + 3 \times 10 = 4 + 30 = 34$$ 5. **Final answer:** A row of 11 squares requires **34** toothpicks.