[alalv]

I think this goes in line with the results in the GRE. In the verbal section it has an amazing 99%, but in the quant one it "only" has an 80%. The quant section requires some reasoning, but the problems are much easier than the river puzzle, and it still misses some of them. I think part of the difficulty for a human is the time constraint, and given more time to solve it most people would get all questions right.