QUESTION:
During their travels, The Mandalorian challenged Baby Yoda with a puzzle. Baby Yoda was given ten sets of ten coins. Each set looks identical, with labelled weights of 1, 2, 3, …, 10 ounces. All of the coins are labelled with the correct weights, except for one set of coins which are all 10% heavier than labelled. The Mandalorian then gave Baby Yoda a highly accurate digital scale, and challenged Baby Yoda to determine the heaviest set by using the scale only once. After a few moments of pondering, Baby Yoda used the scale, and correctly identified the heaviest set. Could you solve The Mandalorian’s puzzle?
ANSWER:
Take the 1-ounce coin from the first set, the 2-ounce coin from the second set, and so on through the tenth set. Place these ten coins on the scale. The digit after the decimal place on the scale reading will identify the heaviest set! For example, if the scale reading is 55.3, we know that the third set is the heaviest since the all the coins from that set are 10% heavier. In other words, the actual weights of the coins would have to be 1 + 2 + 3.3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55.3.
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