If u bring 10 empty bottles to the bottle shop, the bottle shop will change 10 empty bottles to 1 drink. if u bring 100 bottles to the shop. how many drinks will you get? "

You will have 10 drinks, because you divide 100 by 10 giving you 10 drinks. 

You'll get 10 drinks. If x is the number of drinks you get, each drink requires 10 empty bottles, and you have 100 empty bottles, it would look like this:

10x = 100 

You can then simply divide both sides by 10 to get 10 drinks.