There are some cookies in a box. The cookies can be put into plates of 2 or 6 with no cookies leftover. When the cookies are put into plates of 13, there are short of 4 cookies on the last plate. If there are more than 40 cookies but less than 60 cookies, how many cookies are there in the box?
If cookies can be put into plates of 2 or 6 with no cookies leftover, the number of cookies is a multiple of 6 as 6 is a multiple of 2.

Multiples of 6 that are greater than 40 but less than 60: 42, 48, 54, 60

Multiples of 13 that are greater than 40 but less than 60: 52
Multiples of 13 (- 4) that are greater than 40 but less than 60: 48

Common number = 48

Number of cookies = 48

Answer(s): 48