Q: You’ve two lengths of fuse, of the kind used for bombs in cartoons. Each will burn for a total of one minute, but burn erratically. Can you use them to measure 45 seconds?
Reveal the solution
The first step is, as in any decent cartoon, to cackle in an evil way while lighting a match. Then light both ends of one fuse and one end of the other. Once the one burning at both ends is burnt out, light the other end of the remaining half-burnt fuse, cackling.