86% is 86/100. In its simplest form this is 43/50.
8.6 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. And, since it is a decimal fraction, there is not another simpler decimal form. Its equivalent, in rational form, is 86/10 = 43/5.
86, like any integer, can be written as a fraction in simplest form by putting it over 1. 86% = 17/25
.86 = 86/100 = 43/50
86% = 43/50
21/86 cannot be simplified.
86% = 43/50
12/86 = 6/43
86/500
86