numbers&arguments

I have a problem to solved and I wonder if excel could help me with.
In a table I have , for example, three numbers , each numbers coresponds an argument

Numbers Arguments
50 x
200 y
300 z

I need to find for any number, the argument or the arguments amount , after the condition:the number for which I want to find the combination of arguments divided by the largest of the three numbers that can divide (50,200,300) , and the difference remained, as at the large number of the other two remaining to reach a number of individuals.

For example:

a) number 450 corespounding with z+3x; that means 300+3*50
b) number 601 corespounding with 2z ; 2*300

Thank you so very much if you figure out haw to solved these problem