630 / 9 = 70
70.2222
70
9
8.75
7.7778
9.8571
7/9 divided by 9/10 can be restated as, 7/9 * 10/9 = 70/81 ---------- the simplest form
7
7/16 divided by 9/10 = 7/16 x 10/9 = 70/144 You invert the divisor fraction, then do a multiplication instead of division.
70
3