Difficulty: Fun
I’m thinking of three numbers.
They are consecutive counting numbers.
When you add the first two numbers together, you get the third number.
What numbers am I thinking of?
Scroll down or click for a hint, or the answer!
Brainteaser hint
What’s the difference between two consecutive counting numbers?
Brainteaser answer
The numbers are 1, 2, 3 as 1 + 2 = 3.
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4 responses
There is a second possible answer.
The numbers are -1, -2, -3 as -1 + -2 = -3.
Nice one!
I guess this one only works if you think negative numbers are counting numbers. (And I guess whether you think it’s okay to be counting down) but it’s still a great answer!
No problems! I love it when people push our puzzles right to the limit. Puzzles can be a bit tricky to write and we sometimes make mistakes, so it’s always nice to get a comment that is adding to the question and not telling us we’ve got it wrong!
Thanks. After posting I realised your intent of counting numbers was likely to limit it to positive numbers.
The fun of many of these brainteasers is in exploring possibilities.
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