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Summary: Learn how to find percents in your head in this free video series. Get mental math tips from these online tutoring lessons.
Sean Salazar has taught in both Schools and Community Centers, specializing in Math and English. Working as a tutor he helped students prepare for math exams by teaching ways to...read more
"Hi! I'm Sean with Expert Village and I'm going to show you tips and tricks for doing math in your head. Finding a percentage of a number can be a little bit tricky, but it helps when you think about it in the right terms. Let's take the number 329 for our example. If we wanted to find 5% of 329, there's an easy method we can use. First, move the decimal point over one place. 329 becomes 32.9. Divide that number by 2 and you'll get 16.45. That's our answer. Pretty simple. Let's try a larger percentage. If we wanted to find 15% of 329, we can start by just finding 10%. We know 10% is 32.9. It's just a simple movement of the decimal. Now, we already know 5% will be 16.45. Add these together and you get 49.35, which is our answer. Let's try 40% of 329 next. There's an easy way to get this one. Multiply 329 by 4. You'll come up with 1316. Slide the decimal place and you get 131.6, which is our answer. Percentages aren't really that different from any other equation in your head. You want to look for the 10s. Finding the 10s makes it easy to slide decimal places over and make the problems a lot less of headache. Whenever you're doing math in your head, the most important part is being able to visualize the numbers. The more you practice, the better you're going to get. "