A store sells boxes of juice in equal size package Garth bought 18 boxes Rico Ball 36 boxes in my 45 boxes what is the greatest number of boxes in each had how many packs did each person by if each box contains the greatest number of boxes possible

I'm not sure I'm understanding the wording of the question, but if it's this:

Juice boxes come in a package with multiple juice boxes in each package. Three people bought 18, 36, and 45 juice boxes. What is the largest possible number of juice boxes per package?

Then the problem is just an involved way of asking what the greatest common factor of 18, 36, and 45 is, and the answer is 9, the difference between 36 and 45, which are both multiples of 9. Note that 18 is also a multiple of 9. One way to find the greatest common factor of three numbers is to factor all of them and find which prime factors they have in common.