total revenue minus total cost equals total profit
Profit maximization To obtain the profit maximizing output quantity, we start by recognizing that profit is equal to total revenue (TR) minus total cost (TC). Given a table of costs and revenues at each quantity, we can either compute equations or plot the data directly on a graph. The profit-maximizing output is the one at which this difference reaches its maximum.
Value-added tax Value-added tax avoids the cascade effect of sales tax by taxing only the value added at each stage of production. For this reason, throughout the world, VAT has been gaining favor over traditional sales taxes. In principle, VAT applies to all provisions of goods and services. VAT is assessed and collected on the value of goods or services that have been provided every time there is a transaction (sale/purchase). The seller charges VAT to the buyer, and the seller pays this VAT to the government. If, however, the purchasers are not the end users, but the goods or services purchased are costs to their business, the tax they have paid for such purchases can be deducted from the tax they charge to their customers. The government only receives the difference; in other words, it is paid tax on the gross margin of each transaction, by each participant in the sales chain.