Cynthia is correct. Lay the full bottles on their (equal) sides, they will drain to half their volume 3/2= 1.5, 5/2=2.5. Pour 1.5 into 2.5 get 4.0.
Cynthia is correct. Lay the full bottles on their (equal) sides, they will drain to half their volume 3/2= 1.5, 5/2=2.5. Pour 1.5 into 2.5 get 4.0.