Ratio variables are a type of quantitative variable that have a true zero point, meaning that zero indicates the absence of the quantity being measured. This allows for meaningful comparisons between values, such as saying that one value is twice as large as another. Common examples of ratio variables include height, weight, and temperature in Kelvin. In addition to having a true zero, ratio variables also support all mathematical operations, including addition, subtraction, multiplication, and division. This makes them versatile for various statistical analyses. For instance, you can calculate the average income of a group or determine the speed of a vehicle in miles per hour.