Not sure how old this article is, but as a math lover, I had to make a tiny correction. By tiny correction, of course, I mean to say Uncle Cecil was completely wrong. Just because you don’t see a connection, doesn’t mean it isn’t there. The key to this riddle is not a “happenstance” closeness of numbers, but, as in many a good trick, misdirection.
$10 X 3 = $30 (Original Total)
$30 - $5 = $25 (Adjusted Total)
$9 X 3 = $27 (Amount sailors paid) - $2 (Amount kept by the bellhop) = $25 (Total hotel receives)
Each sailor paid $27 but two should have paid a dollar less (or however you want to do the math) and the hotel gets exactly what it should. Works the same in the example given by Cecil.
$15 X 3 = $45 (Original Total)
$45 - $20 = $25 (Adjusted Total)
$14 * 3 = $42 (Amount sailors paid) - $17 (Amount kept by the bellhop) = $25 (Total hotel receives)
The amount used in the original riddle gives a close enough total to make one think the dollar is missing, but what they really missed is the fact that they are working toward the wrong total.