To determine the total percentage increase in the investor's stock account, we can follow these steps:

1. Calculate the new value of each company's stock:

• Company A's new value: $\text{New value of A} = \text{Old value of A} \times (1 + \text{Percentage increase in A})$ $\text{New value of A} = 4060 \times (1 + 0.20) = 4060 \times 1.20 = 4872$

• Company B's new value: $\text{New value of B} = \text{Old value of B} \times (1 + \text{Percentage increase in B})$ $\text{New value of B} = 5800 \times (1 + 0.25) = 5800 \times 1.25 = 7250$

2. Calculate the total value of the stocks last year and this year:

• Total value last year: $\text{Total value last year} = 4060 + 5800 = 9860$

• Total value this year: $\text{Total value this year} = 4872 + 7250 = 12122$

3. Calculate the total percentage increase:

The total percentage increase can be calculated as: $\text{Percentage increase} = \left( \frac{\text{Total value this year} - \text{Total value last year}}{\text{Total value last year}} \right) \times 100$ $\text{Percentage increase} = \left( \frac{12122 - 9860}{9860} \right) \times 100$ $\text{Percentage increase} = \left( \frac{2262}{9860} \right) \times 100 \approx 22.9\%$

Final Answer:

The total percentage increase in the investor's stock account is 22.9%.

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Would you like further clarification or to explore similar examples?

Related Questions:

1. How would the result change if the percentages were different (e.g., 15% and 30%)?
2. How do you calculate the percentage increase when additional investments are made during the year?
3. What formula is used for weighted percentage increases in financial portfolios?
4. What if the investor sold part of their stocks during the year—how would that affect the calculation?
5. How can this calculation be automated for multiple stocks?

Tip:

When dealing with percentage increases in combined accounts, always consider the weighted contribution of each component to the overall portfolio.