Question

The cost price of 12 candles is equal to the selling price of the 15 candles. Find the loss percent

Answer 1

$CP \: of \: 12 \: candles = x \\ \\ SP \: of \: 15 \: candles \: = \: x \\ \\ CP \: of \: 12 \: candles = \: SP \: of \: 15 \: candles \\ \\ CP \: of \: 1 \: \: candle \: = \frac{x}{12} \\ \\ SP \: of \: 1 \: candle = \frac{x}{15} \\ \\ Loss = CP - SP \\ \\ \ = \frac{x}{12} - \frac{x}{15} \\ \\ = \frac{5x \: - 4x}{60} \\ \\ = \frac{x}{60} \\ \\ = \frac{x \div 60}{x + 12} \times 100 \\ \\ \ = \frac{12}{60} \times 100 \\ \\ Loss = 20\%$