What`s the average CS the one can get in 10 minutes , 15 minutes and 20 minutes for his solo top , ADC bot , mid and jungle ?

a number you shouldn't worry about since you'll think too hard about achieving it and subsequently fail at getting.

Try going for 10 cs a minute. (100cs at 10 minutes)

It's difficult but it's a good goal.

Thing is that those are all pretty different situations, as an ad carry: shoot for about 10 a minute in almost every case. But top lane and jungle really depend on your champion and the enemy team comp.
As a jungle, if you're ganking a lot, your cs will be **** but you'll probably have a kill and a few assists under your belt that will offset your lack of CS. Jungle CS varies heavily from game to game even in high elo, some games ill see a jungle with 40 cs at 10 min (but with 3 or 4 assists/kills), other times I see them with almost 100 cs at 10 min (with maybe 1 assist/kill). It really depends on what you can do based on team positions and compositions.
As a top laner it'll vary again but not because of the enemy team comp but because of who you're playing. Some top laners really don't need farm, they just need levels. Renekton is a good example, after getting a brutalizer he's good for farm until mid-late game when he gets tanky. Other top laners need a LOT of farm, like nasus for fairly obvious reasons.

from watching streams of people who are good, 100cs/15min means you're doing alright considering enemy harass and whatnot

100 cs/ 10 min is very good compared to the average player. but for pros its more around 130 at that time since they never miss any creeps

Thanks every one ,,
answers was helpful $$$

Cs wins games son. Lol

Not gonna repeat what everyone else says, but if you're having trouble with your cs, try making a custome and practice last hitting with your most used champs. Get to realllly know their auto attack and how much health they take per item/level.

Like I said, cs wins games.

70 cs at 10 mins is pretty good already if you do it a lot. Considering the enemy champion will try to harass you and keep you from getting more cs.

110+ cs at 10 mins is generally only doable if you are solo mid and you take both your wraiths and enemy wraiths every couple of mins.

For comparison, 114 cs at 10 mins is the max if you get every single creep in lane.

this is dependant of the agressiveness of yourself and your opponent, your jungler and the enemy jungler. in a passive farm lane, 100 cs / 10 minutes is what you should go for