Programmed Math/Decimals

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Decimals (or floating point numbers) are the oposite of fractions, where fractions take the form of a number over a number eg: which is one half.

In decimal format this would be 0.5. Why?

Well one half of 1 is 0.5 since 0.5 * 2 is equal to 1. If we multiply the number at the bottom by the decimal we should get the number at the top. Such as:

Is still one half. since and

So the formulae could be: and thus

Dividing Decimals[edit | edit source]

Division by decimals is similar to dividing by whole numbers.

Rebecca enjoys pushing her scooter around the City-park pond after school and on weekends. If she circles the pond 7 times and total distance of 5.88 km, what is the distance around the pond?

To divide a decimal by a whole number, divide the dividend, disregarding the decimal point. Then place the decimal point in the quotient directly above the decimal point in the dividend.

Steps for Diving with Decimals[edit | edit source]

The problem of 8 divided 4 was easy enough. We're dealing with two whole numbers, so we just separated 8 into 4 groups to end up with 2 in each group. But what if we have decimals in our division problem? A decimal is a fraction of a whole number written as with as a number with a decimal point. 0.25 is an example of a decimal number.