How do you convert 8/17 into a percent and decimal?

1 Answer
May 10, 2016

Decimal representation is a periodic decimal fraction:

8/17 = 0.47058823529411764705882352941176...
with period 4705882352941176

As an approximate percentage,

8/17 ~~ 47.06%

Explanation:

First of all, you have to convert it into decimal by actually dividing 8 by 17 (in this case the result is periodic decimal fraction, so we can do it only approximately):

8/17 = 0.47058823529411764705882352941176...

As you see, 4705882352941176 is a period that is repeated infinite number of times.
So, you may express it using [...] to signify a period as
8/17 = 0.[4705882352941176]

Next, you have to decide about precision since it's not practical to carry too many digits. Assume, you decide that for your calculations it is sufficient to have a precision of 0.0001. Then you round the above number to 0.4706. Notice that the fourth digit after a decimal point 5 is rounded up to 6 because the following digit is 8.

Lastly, to convert a decimal fraction into percentage, you just multiply it by 100, effectively shifting the decimal point two places to the right:
0.4706 = 47.06%.