Melody:WoW Zamarroncis
What a great comprehensive answer!
I actually didn't understand all of what you were trying to tell me but you sound like a budding mathematician!!
It wasn't intended to be a trick question.
I wanted to know which numbers could be divided by 10 leaving no remainder.
and, you did point out that if a number has a Zero on the end then it is exactly divisable by 10.
That's the answer I was after!
Now,
Even numbers are 0,2,4,6 and 8
you also pointed out that if a number ends in an even digit then it is divisable by 2.
great now we have 2 easy ones
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What about 5, how do we tell if a big number is exactly divisable by 5? (We don't want to do the actually division)
Guest:Well, if I have a big number like 234, it is the same as 2x100 + 3x10 + 4 = 2x99 + 3x9 + 2 + 3 + 4.
The part 2x99 + 3x9 can obviously be divided by 9.
So if we can also divide 2 + 3 + 4 (the sum of the digits) by 9, the whole number can be divided by 9.
Walt:Ya I'm sure there is, but this is just the way that I thought about it. I tend to overcomplify things and its not always good, but hey. It works!
Walt:If the last 2 digits of a number are a multiple of 4, the whole number is divisible by 4. For example, 5784 is divisible by 4 because the last 2 digits, 84 is a multiple of 4.
I like Serena:Hmm, if I have a big number like 3456, it can be written as 3x1000 + 456.
3x1000 and numbers with more zeroes are obviously divisible by 8.
In other words, if the last 3 digits are divisible by 8, the whole number is divisible by 8!
Yay!