Problems from Another Time

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

The frustum of a circular cone has height 15.

If an equilateral triangle whose area is equal to 10,000 square feet be surrounded by a walk of uniform width, and equal to the area of the inscribed circle, what is the width of the walk?

Multiplying Like Rabbits

Assume that the human population after the flood was 6 and that 200 years later the population was 1,000,000. Find the annual rate of growth of the population.

Lunchtime at the Fish Pond

A fish sees a heron looking at him from across a pool, so he quickly swims towards the south. When he reaches the south side of the pool, he has the unwelcome surprise of meeting the heron.

Dimensions of a Box

The dimensions of a rectangular box in inches are expressed by three consecutive numbers. The surface of the box is 292 square inches. Find the dimensions.

A Tower on a Cliff

A cliff with a tower on its edge is observed from a boat at sea; find the height of the cliff and the tower.

Dealing in Sheep

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?

Horse of Course

One person possesses 7 asava horses, another 9 haya horses, and another 9 camels. Each gives two animals away, one to each of the others.

The Amount of Time a Man Can Do Work

How long does it take a single man to do work when...

A Serious Series

Given the fraction ax/(a-x), convert it into an infinite series.