Thursday, January 03, 2008

NPR Sunday Puzzle (Dec 30): And what does 2 + 0 + 0 + 8 equal?

NPR Sunday Puzzle (Dec 30): And what does 2 + 0 + 0 + 8 equal?:
Q: Take the equation 5 + 5 + 5 = 550. Make this equation true by adding a single line. Hint: The answer is not to put a slash through the equal sign to make it not equal.
I was excited to see a math puzzle this week, but then I realized it was an old math puzzle I'd seen many times before. You can probably find it if you look. An additional hint, you can't touch the equal sign at all, so don't get any ideas of changing it to ≤.
Edit: Time to reveal the answer since it is after the deadline:
A: Add a line to one of the plus signs to make it look like a 4:
5 4 5 + 5 = 550


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