Brainteasers
Christmas 2025 Newsletter
The Santa Number Sum
Every year, elves add candles shaped like each digit of Santa's age to his cake. The sum of these digits is called a "Santa number" (e.g., the Santa number of 723 is 7 + 2 + 3 = 12).
The Challenge: What is the sum of the first 99 Santa numbers (the Santa numbers of 1, 2, 3, ... to 99)?
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Answer: 900 (The digits 0-9 appear an equal number of times, 20 times each, when listing numbers 1-99. So the sum is 20 x (0+1+2+3+4+5+6+7+8+9) = 20 x 45 = 900).
The reindeer problem
Cupid, Dasher, Dancer, and Vixen, were playing games on the computer one foggy night while Santa sat reading by the fire. Suddenly there was a loud crash followed by lots of reindeer shouts. Santa jumped up to find out what was going on and found the computer monitor on the ground, surrounded with broken glass.
Dancer and Dasher spoke almost at the same time. Dasher said, “It wasn’t me!!” Dancer said, “It was Vixen!!” Cupid yelled, “No, it was Dancer!” With a straight face Vixen said, “Dancer’s a liar.” Only one of them was telling the truth, and the other three were lying, so who knocked over the monitor?
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Answer:Vixen was telling the truth. Dasher knocked over the monitor.
If only one of the four was telling the truth, that means that the other three were lying. By using deductive reasoning, one would conclude that the only possibility with the presented facts is that Dasher was lying when he said, “It wasn’t me!” Dancer was lying when he said, “It was Vixen.” And Cupid also liked when he said, “No, it was Dancer.” This leaves Vixen as the truth-teller, revealing Dasher as the culprit, having stated a direct lie when he said, “It wasn’t me!
And finally..
The Christmas Present
A broken Drum is the best Christmas present to buy someone. Why?
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Answer : It can’t be beaten…. Ho! Ho! Ho!
