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Mental percents

Mental percents

- [Instructor] So let me ask you a question. Can you do percent calculations in your head? If not, this video is for you. We're going to talk about how to easily calculate percents of a number and learn some common fraction to percent equivalents. So if you're British, hopefully you don't think this means crazy percents. Mental percents I mean percents that you can do in your head. So let's say we go out to dinner. Our dinner bill is 68 bucks and 93 cents. We want to leave a 20% tip because we're good tippers and we're in the US. I don't know if this makes any sense to those of you who are in different countries, but in the US, a 20% tip is considered good for service. Well, how do we do that without taking out our calculator? All we really have to do to take 10% of a number, we just have to move the decimal one to the left. So to take 10% of 68.93, we just move this decimal one and we end up with 6.893 and that's 10% of our bill and then we can just double that, maybe we'd round it…

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