I hope this is the correct forum, if not I will move it to the correct on if someone will point it out

I have a finished liquid chemical product in a 55gal drum weighing 450lbs made up of 3 ingredients. These ingredients are stored in 5 gal buckets weighing 40 lbs each.

In order to make 1 drum:

Ingredient A = we use 1/3 (13.33lbs) of the 5gal/40lb bucket

Ingredient B = we use 1/4 (10lbs) of the 5gal/40lb bucket

Ingredient C = we use 1/8 (5 lbs) of the 5gal/40lb bucket

remainder of the drum contains water.

We can carry 64 buckets in a trailer. I need a formula to determine how many of those buckets would ingredient A, ingredient B and ingredient C. And how many drums that would create.

Also in the near future we believe the Ingredient A will change from 13.33 lbs to 10 lbs or 1/4 (10lbs) of the 5gal/40lb bucket. So I need to plug that into one for the furture

I have tried to figure out how to create this math formula and simply can't do it. Any help would be greatly appreciated.