Mixology
by Kevin J. Lin
Hanging about in your favorite pub, you are have a half pint of stout in front of you. Your companion across the table has a half pint of lager. Your friend is as much of a puzzle enthusiast as you are, and he or she offers this challenge:
"If I take a jigger of my lager and pour it in your stout, mix it, then take a jigger from your glass and pour it in mine, will there be more lager in your stout than there is stout in my lager, or vice versa?"
Assume that the two liquids are completely miscible, have the same density and as fluids behave identically.