Haskell will tell you that toRational 0.1 = 3602879701896397 % 36028797018963968 toRational 1e50 = 100000000000000007629769841091887003294964970946560

Haskell will tell you that toRational 0.1 = 3602879701896397 % 36028797018963968 toRational 1e50 = 100000000000000007629769841091887003294964970946560 % 1 Both of those values are precise, although I admit the first isn't really useful for human beings.