7/25 is seven twenty-fifths of the way from 0 going toward 1.  So you have
to make a mark somewhere in between 0 and 1 which you estimate is 7/25ths of
the way from 0 toward 1.  One way to get it accurate is to make a number line
with 25 little marks between 0 and 1.  Each mark will be one twenty-fifth. So
count 7 of those little marks past 0 going toward 1 and put a mark there and
that will represent seven twenty-fifths, like this:

 --------------------------------⚫-------------------------------------------
-1                        0                        1                        2

But you can just estimate where to put the mark.  You know that 7/25ths is
less than half way between 0 and 1, so it will be closer to 0 than it is to 1.
You can change it to adecimal 0.28 which rounds to .3 which is about a third of
the way.

Edwin