Suppose that the volume of two bottles of drinks A and B is X ml, and the volume of the spoon is y ml (x >; y & gt0)。

Step 1: A scoops Y ml into B, and the content of A in B cup is y/(x+y).

Step 2, the volume of B is y[x/(x+y)] in the Y ml beverage scooped out from B with a spoon.

After pouring into bottle A, the content of B in bottle A is y[x/(x+y)]/(x-y+y)=y/(x+y).

It can be concluded that the content of B in A is the same as that of A in B. ..

After repeated operations, the result will not change. The idea that the whole can be substituted is to treat the liquid after the first round of mixing as a whole, so it can be understood.

If countless operations are carried out, the result of finding the limit is that the proportion of coke and sprite in both bottles is 50%

And if the drink in the bottle is just full of one cup, then mixing once is the limit result of 50% each.