Problems from Another Time

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

Pair of Numbers

There are two numbers whose sum equals the difference of their squares.

To Know a Little

To find three quantities x.y, and z...

Four Circles in a Square

In a given square, inscribe 4 equal circles so that...

Neither Rain nor Sleet nor Snow

If two Post-Boys, A and B at 59 miles distance from one another, set out in the morning in order to meet...

Swinging Pendulum

Given a pendulum as shown. The height of the pendulum is two units and its horizontal width is 2 units. What is the area of the pendulum?

Four Numbers

Given four numbers whose sum is 9900; the second exceeds the first by 1/7 of the first...

Sides of a Rectangle 2

In a rectangle, given the diagonal and perimeter, find the sides

Cow Dilemma

Suppose that for every 4 cows a farmer has, he should plow 1 acre of land, and allow 1 acre of pasture for every 3 cows; how many cows could he keep on 140 acres?

Peano on Wronskians: A Translation

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

The Rat Race

Now there is a wall 5 feet thick and two rats tunnel from opposite sides.