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4 More FAQs about Percentages

How do you quickly calculate 25 percent of a number? Or 33 percent of a number? And how can you quickly calculate percentage increases?

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We here at the Math Dude ranch get numerous questions every week from math fans around the world. By far the most common questions we receive have to do with calculating percentages. In particular, how to quickly calculate percentages in your head. You know, things like: What’s 25% of $14,000? Or what’s the final price after a 33% discount on a $25 item? Or what’s the percentage increase from 30 to 40?

It’s not hugely surprising that this is such a popular line of questions since people in lots of different industries love to express changes in terms of percentages. So today we’re going to take a look at four of the most frequently asked questions about percentages.


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