In reply to WB:
It depends so much on the rock type, grade and route style that it's impossible to generalise. For example, climbing on Cornish granite I'll usually take 7 or 8 hexes of varying sizes, and a double or even triple set of large nuts, but I'd not bother with any on slate...
So, somewhere between 10 and 50 nuts from RP0 to 10, somewhere between 0 and 8 hexes, up to 10 cams between my yellow zero (the cam of fear) and a size 6 camelot for those offwidth horrors, between 6 and 20 quickdraws of varying lemgths, and some slings and screwgates/HMSs (more for mutlipitch. Occasionally I might also take a skyhook, some tricams, an extra krab of tiny nuts (including a ballnut) or a big bro, depending on what I think I might be facing.
Usually I just take as much as I can fit on my harness...