In Nigeria, the price of petrol changes all the time. Likewise, in the United States, gasoline price also changes all the time. They might go down for a period of time, but then they usually rise again. One thing that stays the same is that the price is not usually a whole number. Instead, it is shown using a decimal point to describe the cost in dollars and cents. We use decimal numbers all the time, especially when dealing with money. In this tutorial, we will explore decimal numbers and how to perform operations using them.