Final answer:
To calculate the profit, we convert the selling price to the same unit as the purchase price, leading to a R5 profit per kilogram of peanuts sold.
Step-by-step explanation:
The question asked is regarding how to calculate the profit made per kilogram when buying and selling peanuts at different prices. The purchase price is R5 per kg and the selling price is R1 per 100g. To determine the cost per kg when selling the peanuts, we need to convert the selling price to the same unit as the purchase price, which is per kilogram.
Since there are 1000 grams in a kilogram, selling the peanuts at R1 per 100g is equivalent to selling them at R10 per kg (10 × R1 = R10). Therefore, if you buy peanuts for R5 per kg and sell them at R10 per kg, your profit per kg would be R10 (selling price) - R5 (cost price) = R5 profit per kg.