On planet Enigma, the residents use a currency called the confusion. There are only two confusion bills on Enigma, one worth $7$ confusions and the other worth $12$ confusions. There are also some coins of smaller value, but each weighs over $10$ kilograms, so they are difficult to carry around.
In how many ways can a resident of Enigma use only bills to purchase a toaster that costs 19 confusions?
(Everybody knows, of course, that vendors on Enigma do not give change, so residents must make their purchases with exact change.)
On planet Enigma, the residents use a currency called the confusion. There are only two confusion bills on Enigma, one worth $7$ confusions and the other worth $12$ confusions. There are also some coins of smaller value, but each weighs over $10$ kilograms, so they are difficult to carry around. In how many ways can a resident of Enigma use only bills to purchase a toaster that costs 19 confusions?
I think nobody is answering this problem because it's so obvious that they suspect a trick.
Well, I'll admit I'm suspicious, too, but I'll take one for the team. I'm going out on that limb.
There is only one way to purchase the toaster ... with one 7-confusion bill and one 12-confusion bill.
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