# Convergence articles

Displaying 641 - 649 of 649

An elementary introduction to Euler squares and how they can be used in teacher training
The answer to the following question is obtained using as optimum strategy-the farmer is getting the "best deal" possible. Can you figure out the solution strategy?...

How Euler resolved the paradox first noted by Maclaurin that nine points should determine a curve of order three, yet two such curves can intersect in nine points

The history of the four color problem with sketches of the attempted proofs in the nineteenth century and an outline of the computer proof of the twentieth century.
Two pages from a 1650 manuscript of the Lilavati of Bhaskara II (1114-1185). The second photo is an illustration of the Pythagorean Theorem.
The story of the negative numbers
A man bought a number of sheep for $225; 10 of them having died, he sold 4/5 of the remainder for the same cost and received$150 for them. How many did he buy?
There is a log of precious wood 18 feet long whose bases are 5 feet and 2.5 feet in circumference. Into what lengths should the log be cut to trisect its volume?
Two travelers, starting at the same time from the same point, travel in opposite directions round a circular railway.