ZedaH

Okay this is just for Prayer but im sure its the same for the other skills too. The XP you gain per zeal will increase every 3 lvls so if 100 Zeal gives you 4 lvls or more, you get more by doing 10 at a time. Allso to note, the xp gain every 3 lvls is by about 8.2%. And if you need les than 10 zeal to hit the next lvl i would sugest doing it 1 by 1, just for the last few zeal :)