1. **State the problem:** An investor has stock in two companies: Company A worth 5550 and Company B worth 1700 last year. Company A's stock increased by 8% and Company B's stock increased by 4%. We need to find the total percentage increase in the investor's combined stock account. 2. **Formula and rules:** The percentage increase for each stock is given. The total value last year is the sum of both stocks. The total value this year is the sum of each stock's increased value. The total percentage increase is calculated by: $$\text{Percentage Increase} = \frac{\text{New Total} - \text{Old Total}}{\text{Old Total}} \times 100$$ 3. **Calculate old total value:** $$\text{Old Total} = 5550 + 1700 = 7250$$ 4. **Calculate new values for each stock:** Company A new value: $$5550 + 0.08 \times 5550 = 5550 \times (1 + 0.08) = 5550 \times 1.08 = 5994$$ Company B new value: $$1700 + 0.04 \times 1700 = 1700 \times (1 + 0.04) = 1700 \times 1.04 = 1768$$ 5. **Calculate new total value:** $$\text{New Total} = 5994 + 1768 = 7762$$ 6. **Calculate total percentage increase:** $$\text{Percentage Increase} = \frac{7762 - 7250}{7250} \times 100 = \frac{512}{7250} \times 100$$ Show canceling common factors: $$\frac{\cancel{512}}{\cancel{7250}} \times 100$$ Calculate the fraction: $$\approx 0.07062 \times 100 = 7.062\%$$ 7. **Round to nearest tenth:** $$7.1\%$$ **Final answer:** The total percentage increase in the investor's stock account is **7.1%**.