Answer:
Not possible.
Step-by-step explanation:
I assume that you want a method to use the cups to come up with exactly 2 5/8 cups of flour.
We can only add and subtract cups. Thus, we can say that we are looking for non negative integers, n, m, k, such that n(1/2) + m(1/4) + (1 1/6)k = 2 5/8. We write this as
n/2 + m/4 + 7k/6 = 21/8
12n + 6m + 28k = 63
2(6n + 3m + 14k) = 63.
But, this is impossible, since the left hand side of the equation is even and 63 is odd.
Thus, we cannot get exactly 2 5/8 cups of flour using only measuring equivalents of 1/2 cup and 1/4 cup and 1 1/6 cups.
We need a certain number of 1/2 cups plus a certain number of 1/4 cups plus a certain number of 1 1/6 cups to equal 2 5/8 cups.
