27) (32 –10) x (20 –15) =
28) (9 x 6) : ( 3 x 9) =
29) (6 +9) x (32 : 4) =
30) (11 – 4) x ( 45: 9) =
31) 50- [( 6 x 8) : ( 12 + 4 )] =
32) 38 +[ 7 x ( 6 + 3) – (17 x 3)] = 33)3 x [5 + (42 : 3 – 9 )] =
34)120 : [ 3 x 15 +( 2 x 7 + 1) =
35) [ 16 + ( 2 +(5 x 3) – (21 :7 +10)=
(só precisa das respostas)