A sack of rice, which is 50 kilograms, costs $50. If David sells it for $1.20 per kilogram, how much will be his profit? Give me reasons, before answering the question
David's revenue for the 50 kilograms of rice is $1.20 x 50 = $60. So, his profit is $60 - $50 = $10. So the final answer is 10.