This can vary a lot a lot from person to person. I generally do not count weight training towards those hours, but for the rest of the sports, if I am doing a 10 hour traiing week, I'll probably spend 7 hours biking, 2.5 hours running, and 0.5 hours swimming. Mine is probably one of the more off-balance schedules. I do not swim much because I am already a strong swimmer from 10 years of competitive swimming and I do not run as much as I should (since its my weakness) because I am easily injured.
If I were coaching an athlete from scratch (no specific background in any sport), I would probably have my 'default' hours at 50-25-25. Then I would modify by more swimming if that's a weakness, less running if there is an injury possibility and all extra hours to biking because biking is a great way to build up that base...

I come from a marathoning background and the hardest thing to accept about triathlon training is the seemingly small number of running miles and hours spent each week. It seems that I fear I won't have the running miles in to be ready for the distances. It is hard sometimes, based on my background, to have faith in crossover training benefits. But, I am getting there and my percentages are probably 50% bike 35% run and 15 % swim.