1. **State the problem:** We want to find the population of Edinburgh after 4 years if the current population is 495000 and it increases at 1.8% per year. 2. **Formula used:** The population growth can be modeled by the compound interest formula: $$ P = P_0 \times (1 + r)^t $$ where: - $P_0$ is the initial population, - $r$ is the growth rate per year (as a decimal), - $t$ is the number of years, - $P$ is the population after $t$ years. 3. **Convert the growth rate:** 1.8% = 0.018 4. **Substitute values:** $$ P = 495000 \times (1 + 0.018)^4 $$ 5. **Calculate inside the parentheses:** $$ 1 + 0.018 = 1.018 $$ 6. **Calculate the power:** $$ 1.018^4 = 1.018 \times 1.018 \times 1.018 \times 1.018 $$ Calculate stepwise: $$ 1.018^2 = 1.036324 $$ $$ 1.036324^2 = 1.0736 $$ (approximate) 7. **Calculate the final population:** $$ P = 495000 \times 1.0736 = 531132 $$ (approximate) 8. **Answer:** The population of Edinburgh after 4 years will be approximately **531132** people.