RS Aggarwal Solutions for Class 8 Chapter 12 "Direct and Inverse Proportions", indirect variation, as one number increases, so does the other. It is also called direct proportion: they're the same thing. In an inverse variation, it's precisely the opposite: as one number increases, the other decreases. It is also called the inverse proportion. As the Chapter is about Direct and Inverse Proportions, Here are some instances where we come across, more items we buy, more the cost is; more the distance covered by a car, more the petrol consumed; more pipes will fill the tank in less time; fewer men take more days to finish the work.