7/12 = 0.84
0.84/36 = 0.0233·
I have no idea math should have been working hade books bye sorry
It is neccesary because you cannot subtract them without having a common denominator so you have to rename 4 1/2
1) -149, -1; -148, -2; -147, -3
2) No, according to the commutative property of addition, it does not matter the order they are put in.
Hope this helps!