1. **State the problem:** We need to find the percentage increase when the price of a flat rises from 112588 to 150867.92. 2. **Formula for percentage increase:** $$\text{Percentage Increase} = \left(\frac{\text{New Price} - \text{Original Price}}{\text{Original Price}}\right) \times 100$$ 3. **Calculate the difference:** $$150867.92 - 112588 = 38279.92$$ 4. **Substitute values into the formula:** $$\text{Percentage Increase} = \left(\frac{38279.92}{112588}\right) \times 100$$ 5. **Simplify the fraction:** $$\text{Percentage Increase} = \left(\frac{\cancel{38279.92}}{\cancel{112588}}\right) \times 100 \approx 0.3399 \times 100$$ 6. **Calculate the final percentage:** $$0.3399 \times 100 = 33.99\%$$ **Answer:** The percentage increase in the price of the flat is approximately 33.99%.