Question: A vitamin supplement is being investigated to learn if it helps kangaroos learn to run a special maze with high walls. Sixteen kangaroos are paired to yield a total of 8 pairs. Within each pair, one kangaroo is selected to receive the vitamin supplement; the other is given a placebo. The kangaroos are then timed as they learn to run the maze. In six of the eight pairs, the treatment kangaroo learned to run the maze in less time than did the placebo kangaroo. If, in fact, the vitamin supplement is of no benefit, what is the probability that six or more of the treated kangaroos ran the maze in less time than his or her placebo counterpart?