Verified answer

Resposta:
A) (+3) + (–5) + (+8) + (+5)

(+3) + (–5) = –2

(–2) + (+8) = +6

(+6) + (+5) = +11

Resposta: +11

B) (+4) + (–3) + (+2)

(+4) + (–3) = +1

(+1) + (+2) = +3

Resposta: +3

C) (+20) + (+3) + (–5) + (+9) + (–2)

(+20) + (+3) = +23

(+23) + (–5) = +18

(+18) + (+9) = +27

(+27) + (–2) = +25

Resposta: +25

D) (+120) + (–3) + (–5) + (–9)

(–3) + (–5) = –8

(–8) + (–9) = –17

(+120) + (–17) = +103

Resposta: +103

E) (–8) + (+10) + (–7) + (–2)

(–8) + (+10) = +2

(+2) + (–7) = –5

(–5) + (–2) = –7

Resposta: –7

F) (+5) + (–2) + (–9) + (–7)

(–2) + (–9) = –11

(+5) + (–11) = –6

(–6) + (–7) = –13

Resposta: –13

G) (+20) + (+18) + (–14) + (–20)

(+20) + (+18) = +38

(+38) + (–14) = +24

(+24) + (–20) = +4

Resposta: +4

H) (–1) + (+7) + (–2) + (–1) + (–4)

(–1) + (+7) = +6

(+6) + (–2) = +4

(+4) + (–1) = +3

(+3) + (–4) = –1

Resposta: –1

I) (–10) + (+20) + (–5) + (+10) + (+15) + (–12)

(–10) + (+20) = +10

(+10) + (–5) = +5

(+5) + (+10) = +15

(+15) + (–12) = +3

Resposta: +3

Explicação passo a passo:

Espero ter ajudado.