Answer :
[tex] \frac{12 {a}^{2} {b}^{3} }{3ab } \\ = \frac{3 \times a \times b \times 4 \times a \times {b}^{2} }{3ab} \\ \\ cancelling \: common \: factors \\ \\ = 4a {b}^{2} [/tex]
Hence answer is 4ab²
Hope it helps...
Hope it helps...Regards;
Hope it helps...Regards;Leukonov/Olegion.