On 2012-06-20, Steve B wrote:
I am pretty good at math, always was. I can do a lot of things in my head.
I love messing with people who can't.
Easy approach to doing percentages in yer head. Stuff like tips,
discounts, etc:
50% off is easy. Divide by two, or one half.
10% is easy. Divide by 10.
60% is merely one half plus one tenth, in this case, 75 + 15.
65% is halving the 10% and adding it to the pile.
18%? Divide by 10, halve the 10%, Halve the 5%, and add 'em all up.
That's only 17.5%, but close enough to 18% fer a tip.
Think in terms of cutting everything in half, then adding it back up.
Even a senile old geezer like myself still has enough brain cells left
to pull that trick off.
nb
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vi --the heart of evil!
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