Lesson Fractions, Decinmals, and Percentages

Hello Everyone! Today we will be discussing the mathematical relationships between fractions, percentages, and decimals.

We will begin with the basics.
As we all know, 1/2 = 0.5 = 50%
From this, we can see that for any one way of writting the value, there are always two other equivilent forms.

From fractions to decimals is a fairly simplistic concept. We only need to divide the denomonator by the numorator.

From here, we can convert the decimal answer to a percentage. We will first do this by setting up a proportion.
Remember, it's always part over whole. (The part of the fraction over the whole; the part of teh percentage over one-hundred percent)

=

So we can use cross multiplication and get

2x = 100
x = 50

Although this method will always work and it's the technically "right" way, we can use a much less time consumeing trick.

Instead of having to set up a proportion and solve for our missiong variable, we can get percentages from decimals by moving back the decimal two places.

EX:
0.5 = 50%
0.25 = 25%
1.36 = 136%
0.326 = 32.6%

And this will always work as well.

We must always to remember to look at percentages as quantities. 100% of a pie is 1 pie. 20% off on a sales tag that reads $10.00 is $2 dollars off. 200% of an apple is 2 apples.

If you have anymore questions about fractions, percentages, or decicimals (or just anything else that's somehow related to mathematics) feel free to e-mail me personally at brittany@flatearthfilms.net.