Fresh grapes contain 90% water in themselves. The remaining 10% is the content. We need to make dry grapes from these fresh grapes. In dry grapes, the ratio of water to content changes drastically, as water evaporates. Now, consider the percentage of water in dry grapes is only 20. ie, Dry grapes contain 80% content and 20% water.
You are given with 20kg of fresh grapes. You are supposed to make dry grapes from these fresh grapes. How many kg of dry grapes can you make from these fresh grapes?
The puzzle is based on ratio and proportion concepts. Even if, you don’t remember these concepts, you can still try to answer them, with mere logic.