There are two glasses, one filled with red liquid (labelled R in the diagrams) and the other with blue liquid (labelled B in the diagrams). The amount of liquid in each glass is the same.
The Two-Glass Puzzle
A well-known puzzle that illustrates the difficulties of thinking logically. Follow steps 1 to 4, then answer the question below.
Step 2
Transfer some red liquid from R to B, either by pouring or spooning. (There is no "trick" to this puzzle, so let's mention that no liquid gets spilt or evaporated,.)
Step3
Mix the red and blue liquid in glass B. (It doesn't matter whether you mix the liquids thoroughly, just a little, or not at all.)
Step4
Now pour liquid from glass B into glass R so that both glasses again have equal amounts of liquid.
The Question Is there more red liquid in glass B or more blue liquid in glass R?