jitna and utna when used in sentences, gives indication of quantity of the matter beinig talked of. It can be anything. they can be used together, they can be used independently as well. Jitna specifies some reference. utna- 'that much' ex jitna diya hai, wah kaafi nahin hai kya? what(ever)(amount of anything) is given, is that not sufficient? jitna diya hai utna kaafi nahin hai? whatever is given that is not sufficient. jitna kaam karoge utna milega. as much u will work that much u will get. the better translation in English would be: U will get as much as u work. jitna kaha utna karo do whatever was asked/ whatever was asked do that much (not more, not less than that; the quantity which was asked, do that much) jitna zyada padhoge, utna achchha hoga. more u study the better. utna achchha hoga- is like that much good it will be. Jitna/utna can become jitne/utne/jitni/utni according to the gender of matter. If i have missed any case then i hope that someone gives better and complete answer.