A bookworm eats a straight way through a encyclopedia consisting of ten parts. Each part has 1000 pages. The bookworm starts on the front cover of the first part and ends on the back cover of the last part. From how many pages did the bookworm eat?

Recently, somebody told: "My grandfather was born on the first sunday of the year. His seventh birthday was also on a sunday!" In which year was this grandfather born?

Suppose you have two bottles with equal perimeter, thickness and height. One bottle is cilindrically shaped, the other one has the shape of a rectangular box with a square shaped bottom. In which of the bottles fits more milk?