The way to get good spherical determine depend in SQL question

In my Postgresql database, the Pupil desk has student_marks and total_marks columns.

I wish to get the share primarily based on scholar marks.

For instance:

student_marks * 100 / total_marks => 118 * 100 / 147 = 80.27 = 80%

If the primary two digits of decimal quantity are beneath 50, ex: 75.49 then it ought to be 75% or if the primary two digits of decimal quantity are equal to 50 or above 50, ex: 67.50 or 67.52 then it ought to be 68% so

This question works for me:

choose TO_CHAR(19.57, 'fm99%') as abc;

it returns 20%.

The issue is of the coed get 100% marks:

choose TO_CHAR(100, 'fm99%') as abc;

returns ##%

Please present me an answer for this or else recommend one other manner to do that.

Thanks.