Question

An average newspaper contains at least 9 pages and at most 46 pages. How many newspapers must be collected to be certain that at least two newspapers have the same number of pages?

Answer 1

There are 46-9 + 1
= 38 possible lengths of the newspaper.
The number of possible combinations of 2 papers with different lengths
= 38*37/2 = 703
So after picking 703 the next pick must be one you’ve picked before
Answer is 704