When the selling price of a good is higher than its cost then, it is called profit. Similarly, when the selling price of goods is lower than its cost price then it is called loss. When there is an investment on Rs. 1000 and the C.P are considered as Rs. 100 and profit or loss is calculated on it, then it is called profit or loss percent. When a marked price of (M.P) of any article reduces and sells to the customer by shopkeeper then the reduced amount is called the discount. When a shopkeeper allows discount from Marked Price (M.P) of any article. When M.P is considered as Rs. 1000 and discount are calculated from it, then it is called Discount percent. Value added tax is a tax charged on the actual selling price of goods. Simple interest is the interest which is payable on the principal.