If x is 200 percent more than y, then what percent of x is y? The answer is 33.3% I don't understand though the reason behind this is since it says that "If x is 200% more than y, then x = y + 200%y. Since 100% of y = y and 200% of y = 2y, we can say that x= y + 2y or x = 3y." But If its 200% more than would it be x=2y? how is it 3y? Biology Section: Can someone give me a definite rule behind natural selection and evolution and their difference? So far I know that evolution acts on population only, while NS is individual(not sure on that one). And that evolution is alleles based while NS is more phenotype centered. I just don't see their difference though apart from that. I mean according to darwin's evolution there is a selection forced from based on environment of the more favorable trait but isn't that just natural selection?