Comment Re:I have heard of a version of this that works... (Score 1) 206
Doesn't work. Just rerun the picture test enough times to deduce that the constant is that you always get cars and flowers, but other items are subject to change. So then by induction, you try one more thing. Three constant things. Well then there are only 6 ways to choose 2 elements. Fine, make all say, 9 pictures constant "things", one of which is a car and one of which is a flower. How many 2-permutations? 72.