remember that (a/b) times (c/d)=(a times c)/(b times d)
also remember that
a times (b times c)=(a times b) times c
therefor
lets say you wanted to do
120/4
remember that 120=10 times 12 and 12/4=3 so
120/4=12/4 times 10/1=3 times 10=30
so you have
3600/9
remember that you try to get rid of the zeroes as much as possible
3600=36 times 100
3600/9=36/9 times 100/1
remember that 36/9=4 because 4 times 9=36 (mulitplication facts)
36/9=4
3600/9=36/9 ties 100/1=4 times 100=400
answer is 400