Dorrie H. 100 Great Problems of Elementary Mathematics

Dover Publications, 1965. — 393 p.Problems that beset Archimedes, Newton, Euler, Cauchy, Gauss, Monge and other greats, ready to challenge today’s would-be problem solvers. Among them: How is a sundial constructed? How can you calculate the logarithm of a given number without the use of logarithm table? No advanced math is required. 100 problems with proofs.