i need help simplifyng this expression

Question

72a^2*b^3/-24a^2*b^5

Answer 1

72/-24 = -3
a^2/a^2 = 1
b^3/b^5 = 1/b^2 so =
-3/b^2

Answer 2

72a^2*b^3
___________
-24a^2*b^5

simplifying you go and reduce then divide the larger by the smaller

4a^2*b^3
___________
-1a^2*b^5

now I divide...a's cancel out and b's subtract since you divide the b's and subtract the larger by smaller b^5-b^3=b^2

-4
___
b^2

Answer 3

I meant -3/b^2 of course.