3)
a)
[tex]90 \div 3 = \Large\boxed{ \green{ \bf \: 30}} \\ \\ 30 \div ( - 2 )= \Large \boxed{ \bf \: - 15} \\ \\ - 15 \div ( - 5) = \Large \boxed{ \green{ \bf \: 3}} \\ \\ 3 \times 30 = \Large\boxed{ \bf \: 90}[/tex]
b)
[tex] - 12 \div 2 = \Large \boxed{ \purple{ \bf - 6}} \\ \\ - 6 \div ( - 3) = \Large \boxed{ \purple{ \bf \: 2}} \\ \\ 2 \div 2 = \Large \boxed{ \purple{ \bf \: 1}} \\ \\ 1 \times ( - 12) = \Large \boxed{ \bf \: - 12} \\ \\ \Large \boxed{\underline{\blue{\bf Bons \:Estudos}}}[/tex]
