Explanation:

- Initial Situation:

- Price of tomatoes increases by 10%.

- Consumption decreases by 15%.

- Expenditure Calculation:

- Let's assume the initial price is 1 unit, and the consumption is 1 unit.

- Initial expenditure = Price × Quantity = 1 × 1 = 1 unit.

- New price = 1 + 10% of 1 = 1.1 units.

- New consumption = 1 - 15% of 1 = 0.85 units.

- New expenditure = New price × New consumption = 1.1 × 0.85 = 0.935 units.

- Percentage Change in Expenditure:

- Change = New expenditure - Initial expenditure = 0.935 - 1 = -0.065 units.

- Percentage change = (Change / Initial expenditure) × 100 = (-0.065 / 1) × 100 = -6.5%.

- Correct Option:

- Option 3: 6.5% decrease