What will the diameter of a sphere be, when its volume and surface area are expressed by the same number?

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

A man has four creditors. To the first he owes 624 ducats; to the second, 546; to the third, 492; and to the fourth 368.

A man hired a horse in London at 3 pence a mile. He rode 94 miles due West to Bristol then due north to Chester, whence he returned toward London for 66 miles, which put him in Coventry.

A tree is 20 feet tall and has a circumference of 3 feet. There is a vine that winds seven equally spaced times around the tree and reaches the top. What is the length of the vine?

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?

A barrel has various holes in it. The fist hole empties the barrel in three days...

A speculator bought stock at 25% below par and sold it at 20% above par. He gained $1560. How much did he invest?

Given: a circle with an inscribed equilateral triangle. The triangle has an area of 12 square units. What is the area of the circle?

Determine the different values of x, when a certain function hits a minimum.

Given a door and a measuring rod of unknown dimensions, the rod is used to measure the door.