To simplify a fraction, you divide the top and the bottom by their
common factor, if they have any.
So the first thing we have to do is figure out whether 35 and 63
have any common factors.
The factors of 35 are 1, 5, 7, and 35 .
The factors of 63 are 1, 3, 7, 9, 21, and 63 .
We don't care about ' 1 '.
'1' is a factor of EVERY number, and it doesn't help anyway.
We could divide things by '1' all day long and nothing would change.
The only common factor besides ' 1 ' is 7 .
So to simplify the fraction, we divide top and bottom by 7 .
35/7 = 5
63/7 = 9
35 / 63 = 5 / 9 .