You add 5/2 tablespoons of olive oil for every 13/8 tablespoons of balsamic vinegar to make 99 tablespoons of bread dip. How much olive oil and balsamic vinegar do you use?

5/2 tbs = 20/8 tbs

20/8 tbs + 13/8 tbs = 33/8 tbs per mixture

99 = 792/8 tbs of mixture needed

792 : 33 = 24 mixtures needed

24mixtures * 5/2 tbs per mixture = 60 tbs of olive oil

and 24 mixtures x 13/8 tbs per mixture = 39 tbs of balsamic vinegar.