How Do I Turn A Percent Into A Fraction And Vice Versa?

80%

"Percent" means "per hundred" (/100). So 20% is 20 per hundred, 20/100.

Once you have a fraction like 20/100, you can simplify it in the usual way. That involves finding factors that are common to the numerator and denominator.

20/100 = (1*20)/(5*20) = (1/5)*(20/20) = (1/5)*1 = 1/5

Note that all of the above equal signs are valid. We have not changed the value of the expression as a result of any of these manipulations.
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To turn a fraction into a percent, you can divide it out (quit when you have enough digits to suit).

1/7 = .14285714285714... (it repeats forever)

Now, multiply this by 1. The 1 is in a special form: 100%. You will have the same value, but it will be expressed differently. The value will be expressed as a percent. (After you do this a few times, you will see that moving the decimal point 2 places is all it takes to allow you to add a % sign.)

.142857*100% = 14.2857%
.143 = 14.3%    (after you gain experience and confidence)

Alternatively, you can express the fraction over 100:

1/4 = (1/4)*(25/25) = (1*25)/(4*25) = 25/100 = 25%

Here, you choose the 25 because you know that will make the denominator=100.

Or, you can go for it right away:

1/6 = (1/6)*100% = (100%)/6 = (100/6)% = 16.667%