How do I convert a decimal number into a fraction?

short answers for big questions

All decimal numbers can be converted into fractions as long as they are rational numbers. For instance, the number `pi` is an irrational number and so it can’t be written as a fraction. The following procedure is not difficult. It starts by putting the decimal part of the number (the digits on the right of the dot) on the numerator of a fraction and we put number 1 as being the denominator. Then, so as to obtain an equivalent fraction without decimal numbers, we multiply the numerator and the denominator by 10, 100, 1000... according to the number of digits of the decimal part, this is, if the decimal part has one digit, we will multiply by 10; if it has two digits, we will multiply by 100 and so forth. Finally, if the obtained fraction is not irreducible, it is simplified. Let’s see some examples so as to be easier to understand the concept:

Convert number 0.2 into a fraction

`(0.2)/1 = (0.2 xx 10)/(1 xx 10) = 2/10 = 1/5`

Convert number 0.75 into a fraction

`(0.75)/1 = (0.75 xx 100)/(1 xx 100) = 75/100 = 3/4`

Convert number 0.625 into a fraction:

`(0.625)/1 = (0.625 xx 1000)/(1 xx 1000) = 625/1000 = 5/8`

Convert number 2,35 into a fraction

`2 + (0.35)/1 = 2 + (0.35 xx 100)/(1 xx 100) = 2 + 35/100 = 2 + 7/20 = 40/20 + 7/20 = 47/20`

cake with slices in fraction

And what will I have to do if I want to convert a number from fraction to a decimal one?

That conversion is much easier! Having in mind that the stroke of a fraction stands for a division, it will be enough to divide the numerator by the denominator if you want to convert from a fraction to a decimal. For instance: `5/2 = 5 : 2 = 2.5`.



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