Hint 1.

In you combine 2/3 bottle of red paint with 4/5 bottle of yellow you get 22/15 bottle of orange.    Let t = the Numer of repetions of 2/3 bottle of red and 4/5 bottle of yellow. Then we would have t = 60    (88   divided by 22/15).    From this determine how many red and how many yellow.



Hint 2.

An alternative.    Consider the RATIO of   red paint to yellow paint.

            2/3 : 4/5  simplifies to  5 : 6    

We need 5 red bottle for each 6 yellow   and a total of 88.


Either of these approaches could be formalized with some algebra.