Final answer:
To find the purchase prices of clocks A and B, we need to establish a system of equations based on the total cost and the profit or loss from selling each clock. However, without knowing the actual selling prices or additional relationships, we cannot solve for the individual purchase prices of the clocks with the information given.
Step-by-step explanation:
The total cost of clocks A and B is RS 650. If clock A is sold for a 20% profit and clock B is sold at a 25% loss, we need to determine the original purchase prices for each clock. Let's denote PA as the purchase price of clock A and PB as the purchase price of clock B. From the information given, we have PA + PB = RS 650 (equation 1).
Now, let's express the selling prices in terms of the purchase prices and the given profit and loss percentages. Clock A is sold at a 20% profit, hence its selling price is PA + 0.20PA = 1.20PA. On the other hand, clock B is sold at a 25% loss, which means its selling price is PB - 0.25PB = 0.75PB. Since the problem does not provide the actual selling prices, we can only setup the relationship between PA and PB.
To find the individual purchase prices of clocks A and B, we need to solve the system of equations composed of the total cost equation and the proportional relations given by the profit and loss percentages. This can typically be done using substitution or elimination methods.
However, since we're not given the actual selling prices or the relationship between them, we cannot definitively solve for PA and PB with the information provided. More information is needed to fully answer the student's question.