BECE Mathematics 2021 Paper

Profit = Selling Price - Cost PriceProfit percent (\%) is the amount of the profit expressed in terms of percentage. The profit is based on the cost price, hence the formula to profit \% is (Profit/Cost Price) $\times 100$But profit $=$ Selling Price - Cost PriceHence profit \% = ([Selling Price-Cost Price]/Cost Price) $\times 100$ From the question, cost price (bought) $=1500$Profit \% = 20\%Selling price $=$ ?Let the selling price be $x$ Get rid of the denominator by multiplying both sides of the equation by the L.C.MEvery number is divisible by 1 , hence $20=\frac{20}{1}$The L.C.M of 1500 and 1 is 1500 , hence multiply both sides by 1500 and cancel out$\;100 \times (x-1500)=20 \times 1500$$\;100 \times x-100 \times 1500=30000$$\;100 x-150000=30000$$\;100 x=30000+150000$$x=1800$Divide both sides by 100$x=1800$