Question

quanto e 20 + [18 + (9 - 5) + 4] - 7

Answer 1

= 20 + [ 18 + 4 +4 ] - 7
= 20 + 26 - 7
= +39

Answer 2

20 + [18 + (9 - 5) + 4] - 7
20+ [ 18 +    4  + 4]  - 7
20 + [ 18  +  8  ] - 7
20 + [18 + 8 ] - 7
20 + [26 - 7]
[20 + 33 ]
      23