CUPS OF MILK

[smclean23]

Four cups of milk are to be poured into a 2-cup bottle and a 4-cup bottle. If each bottle is to be filled to the same fraction of its capacity, how many cups of milk should be poured into the 4-cup bottle?
(A) 2/3
(B) 7/3
(C) 5/2
(D) 8/3
(E) 3

[TRANGZON]

The same fraction of the capacity 1/a

1/a x 2 + 1/a x 4 = 4

--> a = 2/3
--> 2/3 x 4 = 8/3 --> D