The incircle O(r) of triangle ABC touches AB at D, BC at E and AC at F. Find r in terms of AD, BE and CF.

Individual problems from throughout mathematics history, as well as articles that include problem sets for students.

A certain man says that he can weigh any amount from 1 to 40 pounds using only 4 weights. What size must they be?

The authors recount the 'great tale' of Napier's and Burgi's parallel development of logarithms and urge you to use it in class.

There is a circle from within which a square is cut, the remaining portion having an area of 47.6255 square units.

A man plants 4 kernels of corn, which at harvest produce 32 kernels: these he plants the second year; now supposing the annual increase to continue 8 fold, what would be the produce of the 15th year, allowing 1000 kernels to a pint?

If an arc of 45 degrees on one circumference is equal to an arc of 60 degrees on another circle, what is the ratio of the areas of the circle?

How a translation of Peano's counterexample to the 'theorem' that a zero Wronskian implies linear dependence can help your differential equations students

A wooden log is encased in a wall. If we cut part of the wall away to a depth of 1 inch...

Knowing the base, b, and the altitude, a, of a triangle. Find the expression for a side of the inscribed square.

Now there are 100 deers [being distributed] in a city. If one household has one deer there is a remainder...Find the number of households in the city.