 Hello and welcome to the session. In this session we will discuss the following question and the question says John buys a refrigerator for $400. The transportation charges are $5 and the inspiration charges are $16. First he then serves it to his friend for $310. Find the last percent. Now before we start solving the question let us first recall the formula for profit or last percent. First let us review the formula for profit. Now profit is equal to selling price minus cost price. The formula for loss is, loss is equal to cost price minus selling price. Now the formula for profit or loss percent is equal to total profit or loss upon cost price into 100. So this is the key idea for this question and using this key idea we will solve the question. Let's start the solution now. We are given that John buys a refrigerator for $400. Also we are given the transportation charges and the installation charges. So the cost price of the refrigerator is equal to $400 plus overheads. Now the overheads is equal to the transportation charges which is $5 plus the installation charges which is $16 and this is equal to $21. So therefore cost price of the refrigerator is equal to $400 plus $21. This is equal to $421. It is also given that he then sells it to his friend for $310. So the selling price of the refrigerator is equal to $310. We will now calculate the loss. Now going back to the key idea we have loss is equal to cost price minus selling price. So loss is equal to cost price minus selling price which is equal to cost price which is $421 minus selling price which is $310. This is equal to $111. Now we have to calculate the loss percent. This is equal to total profit or loss upon cost price into 100. So in this case we have the loss is equal to $111. The cost price is $421 into 100. This is equal to 26.36%. So the final answer is loss percent is equal to 26.36%. With this we end our session. Hope you enjoyed the session.