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MathsIsFun
2005-02-13 09:47:43

Percentages just mean "per 100" so 20% means "20 per 100"

Your particular problem MAY be as simple as calculating 20% of 3500, (which is 20/100 x 3500 = 20 x 3500/100 =  20 x 35 = \$700)

But perhaps they mean "there was a price, Joe got 20% of that, and the total is \$3500"

In that case it is a little harder.

You would figure it this way: you know that \$3500 = "The Unknown Price" + 20% of  "The Unknown Price" =  120% of the unknow price.

And 120% is 120/100, which is really just 1.2

So, "The Unknown Price" x 1.2 = 3500

Dividing both sides by 1.2 gets:

"The Unknown Price" x 1.2 / 1.2  = 3500 / 1.2

"The Unknown Price" = 3500 / 1.2

"The Unknown Price" = 2916.67

And Joes 20% would be 20/100 * 2916.67 = 583.33

(Confirming this: 2916.67 + 583.33 = 3500)

Was that a help?

msg21252
2005-02-13 04:12:43

need formula on how to figure percentages from a whole number example:  total amount for item is \$3500.00, Joe's 20% is included in this number. How much does Joe get?

MathsIsFun
2005-02-11 07:38:56

A 3D cube is just a simple box. So it has a top and a bottom, a front and back and a left and right side. In othe words just 6 sides. But if you count the edges, there are 12.

You can find out more here: Platonic Solids

Barker
2005-02-11 04:48:37

My daughter's homework is can you write down the properties of a cube?  It is a 3D cube.   Is the answer 12 sides.

MathsIsFun
2005-02-10 20:11:01

Well, we like this website! (Of course)

We have some pages here that tell you how to deal with fractions. Adding, subtracting multiplying and dividing.

For example, to multiply 1/4 by 2/3 you just multiply the top bits by the bottom bits:

1/4 x 2/3 = 1x2 / 4x3  = 2/12.

2/12 can be simplified to 1/6