This is the title page of the geometry book of Jacob Kobel (1460 - 1533). The book dealt primarily with measurement, showing its readers how to use various instruments to measure fields, determine heights of buildings, and perform various other necessary tasks.
Two ants are 100 paces apart, crawling back and forth along the same path. The first goes 1/3 pace forward a day and returns 1/4 pace; the other goes forward 1/5 pace and returns 1/6 pace. How many days before the first ant overtakes the second?