Dorrie H. 100 Great Problems of Elementary Mathematics. 1965.
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.