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Percents  Concept
Alissa Fong
Alissa Fong
MA, Stanford University
Teaching in the San Francisco Bay Area
Alissa is currently a teacher in the San Francisco Bay Area and Brightstorm users love her clear, concise explanations of tough concepts
Percents can be confusing, but there are methods we use to make them easier for us. Percents can be rewritten as fractions, or proportions, or as decimals. We can use multiplication and division to find percentages or portions of different items. These methods are used often in money problems and other word problems.
You guys started to learn about percents early in Elementary School when you were first looking at fractions. But sometimes it can get really confusing like what was the percent and where is the decimal and how many spots do I move it and all that stuff. When I deal with problems having to do with percents I remember the simple proportion, if I can remember "is over of equals percent over a hundred" that's a way you can set up pretty much any percent problem that you're going to come across in your high school career. Percents by the way also show up lots of times on standardized tests, high school exit exams, maybe even on the SAT or ACT so look out. Again if you can remember "is over of, equals percent over a hundred" that'll help you a lot when you're working with percents. Also it's really important you know how to work between fractions, decimals, and percents. For example if I had the fraction one fourth, that means one divided by four. So on your calculator you could type in there one divided by four and you will get zero point two five. To turn that into a percent, percent means out of a hundred I would multiply zero point two five by a hundred which is the same thing as moving the decimal place two spots to the right so I could write this as 25%. It's really important you guys are able to move back and forth between all these different representations, it's the same value just written with three different forms.
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Alissa Fong
M.A. in Secondary Mathematics, Stanford University
B.S., Stanford University
Alissa has a quirky sense of humor and a relatable personality that make it easy for students to pay attention and understand the material. She has all the math tips and tricks students are looking for.
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Comments (3)
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Bruce · 3 weeks, 6 days ago
this video is so helpful. Thanks a lot!
Mr · 7 months, 3 weeks ago
Hi but why isn't this free? You can get all this from Youtube for free except just from different teachers?
shimunov · 1 year, 7 months ago
what i learned is to find percent, example: 20%of50. i would do first 20 multiplied by 50=1000 then you divide by a 100=10