1. **State the problem:** A phone originally priced at 120000 has increased to 124800. We need to find the percentage increase. 2. **Formula for percentage increase:** $$\text{Percentage Increase} = \left(\frac{\text{New Price} - \text{Original Price}}{\text{Original Price}}\right) \times 100$$ 3. **Substitute the values:** $$\text{Percentage Increase} = \left(\frac{124800 - 120000}{120000}\right) \times 100$$ 4. **Calculate the difference:** $$124800 - 120000 = 4800$$ 5. **Divide by original price:** $$\frac{4800}{120000} = 0.04$$ 6. **Multiply by 100 to get percentage:** $$0.04 \times 100 = 4$$ 7. **Final answer:** The price increased by **4%**.