4878.583 cannot be expressed as a fraction over 12 because 0.583 is not a fraction over 12.
17/12 = 1 5/12
10/12 is a fraction that is less than 1. It cannot sensibly be changed to a mixed fraction.
12/11 = 11/11
18/12 is an improper fraction. It's equivalent to the mixed number 1.5 .
A common fraction like 5/12 is not normally expressed as a mixed number
It can't be one. Mixed numbers are greater than 1.
125 over 10 equals 12 1/2
it would be 12 and four fifths
25/2 = 12 1/2
They can't be simplified as a fraction, but can be changed to a mixed number to give 5 and 7 over 12.
13/12 is already a simplified fraction. It can be expressed as a mixed number as 11/12
12.13 as a mixed fraction is 12 and 13/100.