What happens if I drop an ant? What books are bad for you? What percentage of the world's water is contained in a cow? The Oxbridge undergraduate interviews are infamous for their unique ways of assessing candidates, and from these peculiar enquiries, professors can tell just how smart you really are. John Farndon has collected together 75 of the most intriguing questions taken from actual admission interviews and gives full answers to each, taking the reader through the fascinating histories, philosophies, sciences and arts that underlie each problem. This is a book for everyone who likes to think they're clever, or who thinks they'd like to be clever. And cleverness is not just knowing stuff, it's how laterally, deeply and interestingly you can bend your brain. Guesstimating the population of Croydon, for example, opens a chain of thought from which you can predict the strength of a nuclear bomb ...and that's just the start of it.