Expressed as a mixed number in its simplest form, 154 percent is equal to 1 27/50 or one and twenty-seven fiftieths.
154 is an integer, not a fraction. It can be written in fraction form as 154/1 though I can see no reason for doing so.
6.16 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 616/100, which can be simplified to 154/25.
154% is 1.54
15.4% =154/1000 = 77/500
If you mean 3 and 7/154 then it is 3 and 1/22 in its simplest form