Răspuns:
(a x 5) : 2 = 40:4
(a×5):2=10
a×5=20 /:5
a=4
42:(dx 3) = 21:3/:21
2:(d×3)=1:3
(d×3)×1=2×3
d×3=6
d=2
(b: 3) x 6 = 52 - 4
(b:3)×6=48 /:6
b:3=8
b=8×3=24
60 - (e x 9) = 30:5
60-6=e×9
54=e×9/:9
e=6
9 x(c:6) = 6 x 6 /:9
c:6=2×2/:2
c:3=2
c=6
72 – 40 = (f: 3) x (40:5)
32=(f:3)×8
f:3=32:8=4
f=12