Modern Magic: A Practical Treatise on the Art of Conjuring

Thus, suppose the throws to be five, two. Five multiplied by two are ten; add five, fifteen, which, multiplied by five, is seventy-five, to which two (the points of the remaining die) being added, the total is seventy-seven. If from this you mentally deduct twenty-five, the remainder is fifty-two, giving the points of the two dice--five and two. But, you will say, suppose the person who threw had reversed the arithmetical process, and had taken the points of the second die (two) as his multiplicand, the result must have been different. Let us try the experiment. Twice two are four, five added make nine, which, multiplied by five, is forty-five, and five (the points of the other die) being added to it, bring the total up to fifty. From this subtract twenty-five as before. The remainder, twenty-five, again gives the points of the two dice, but in the reverse order; and the same result will follow, whatever the throws may be.