Given a rectangle, find the line through one vertex of minimum length that passes through the extensions of the two opposite sides.

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

Show that the curves x2 - y2 = a2 and 2 xy = b2 cross at right angles.

Two men have a certain amount of money. The first says to the second, "If you give me 5 denari, I will have 7 times what you have left."

There is a right triangle where: the sum of the upright multiplied by itself twice and the hypotenuse multiplied by itself is 700 units; and, the sum of the base multiplied by itself twice and the hypotenuse multiplied by itself is 900 units.

Three men wish to buy a horse but none have a sufficient amount of money for the purchase; to do so they must borrow from each other. How much money does each man have and what is the price of the horse?

If I were to give 7 pennies to each beggar at my door, I would have 24 pennies left in my purse. How many beggars are there and how much money do I have?

A horse halving its speed every day runs 700 miles in 7 days.

What is the perpendicular height of a cloud when it's angles of elevation were 35 degrees and 64 degrees as taken by two observers?

How much does Landowner A give to each worker knowing Landowner B gives a certain amount more and has few workers.

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