The numbers are smaller.
The simplest form has the smallest numbers and so may be easier to manipulate.
Write as a fraction in simplest form
When a fraction is written in simplest form, it's easier to perform operations on that fraction. For instance, multiplying (1/5) and (2/3) is easier than multiplying (25/125) and (18/27).
It is as a fraction in its simplest form: 11/16
As a fraction, 901/1000 can't be simplified,but it may be easier to write " 0.901 ".
0.196 as a fraction in simplest form is 49 ------ 250
0.409 as a fraction in the simplest form is 409/1000
0.32 as a fraction in simplest form = 8/25
0.84 as a fraction in simplest form = 21/25
3.1818 as a fraction in simplest form = 15909/5000
0.31 as a fraction in simplest form = 31/100
0.4875 as a fraction in simplest form is 39/80