Quote:
Originally Posted by patteeu
They should be able to recognize that it's divisible by 3 if they know the simple "trick" that any number whose digits add up to a number divisible by 3 is, itself, divisible by 3. I'm sure you and frosty are well aware of this, but just in case, I thought I'd mention it.
2+0+0+7=9
9 is divisible by 3, therefore 2007 is divisible by 3.
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Never seen this trick before. Why aren't we taught all the tricks in school? Might help.