Answer:
According to a nationwide experiment conducted in 2001 involving over 1,000 schoolchildren and 21,000 drops of toast, the theory was confirmed: toast that falls off a plate land with the butter-side down two-thirds of the time. Contrary to widespread belief, it has absolutely nothing to do with one side of the sandwich being buttered. In this case, the toast begins to rotate as soon as it crosses over the edge of the plate; however, because of the slow spin rate, it does not rotate quickly enough to bring the butter-side up again before the toast hits the floor.
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