The camel-sharing puzzle asks how a herd of 17 camels should be divided among three children who have inherited it. The will stipulates that the first child is to inherit half the herd, the second a third and the last a ninth.
The problem is that 17 is prime: it is not divisible by 2 or 3, let alone by 9. And cutting up the camels is obviously not an appealing option…
Faced with this seemingly insoluble problem, the heirs consult a wise man, who offers them a solution as elegant as it is unexpected: he lends them an eighteenth camel and suggests dividing up the enlarged herd. The first child therefore receives half of 18 camels (that is, 9), the second a third of 18 (that is, 6), and the last a ninth of 18 (that is, 2). Together, they have thus received 9 + 6 + 2 = 17 animals, allowing the wise man to take back the extra camel he lent them!
What happened mathematically?