Calculating Percentages

One of the things that I learned how to do this year in math class was to calculate the percentage of something.

I made a video using the calculator on my phone today to see if I could prove that I know what I am doing when it comes to calculating percentages:




So did I do it right?  

I THINK I did.  What I always try to remind myself is that I'm multiplying by a two digit decimal number.  So if I want seven percent of something, I multiply by .07.  That makes sense because percent means "a part of 100," and two digit decimals represent "hundredths."


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