Final answer:
Upon selling two toasters at a 20% profit and a 20% loss, there is no overall gain or loss as the total selling price equals the total cost price, making the profit and loss percent on the whole transaction 0%.
Step-by-step explanation:
The question involves calculating the overall gain or loss on two transactions involving equal percentages of profit and loss but on different bases, which is a common question in profit and loss problems in mathematics. To calculate the gain or loss, we need to find the effective percentage change when a number has two successive changes of x% and -x%.
Let the cost price of each toaster be Rs. 900.
On the first toaster, a 20% profit is made, so the selling price of the first toaster will be:
Cost Price + Profit = 900 + (20/100 * 900) = 900 + 180 = Rs. 1080
On the second toaster, a 20% loss is made, so the selling price of the second toaster will be:
Cost Price - Loss = 900 - (20/100 * 900) = 900 - 180 = Rs. 720
The total cost price of both toasters is 2 * 900 = Rs. 1800, and the total selling price is 1080 + 720 = Rs. 1800. Therefore, there is no gain or loss on the whole transaction when considered together. The profit and loss percent on the whole transaction is 0% because the total cost price equals the total selling price.