5.25 is, itself, 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. Its equivalent, in rational form, is 525/100. You can simplify this rational fraction if you so wish.
21/4
0.525 written as a fraction = 525/1000
tl
525% = 21/4
It is 525/1 inches.
It is 525/1 grams. If you want it expressed as a fraction of some other quantity then you need to specify the second quantity.
525/1
525/1000 = 21/40
525 = 525/1, although I see no reason why anyone would wish to write it like that.
1.3125
525% = 5.25 = 525/100 = 21/4 = 51/4
2/5
what is the 0.0625 converted as a fraction