4ème3 2010-2011
Exercices sur le chapitre 1 Exercices sur le chapitre 1
Exercice 3. b/ page 6
H=–6––2=–62=–4
I=5–8=5–8=–3 ou I=5–8=–3 K=–8–15=–8–15=–23
L=7–3=7–3=4 ou L=7–3=4
Exercice : soustraction de relatifs A=–4––12=–412=8 B=5–12=5–12=–7 C=–11–10=–11–10=–21 D=–514=9
E=–7–3,5=–7–3,5=–10,5
Exercice n°3 p 14 A=–1×8=–8 B=–1×–6=6 C=–4×1=–4 D=7×1=7 E=1×–3=–3 F=–1×–2=2
Exercices : addition, soustraction ou multiplication A=–5––12=–512=7
B=–7×14=–98 C=12–17=–5 D=–517=12 E=–5×–12=60 Exercice 5 page 14
A=–7–8=–15 B=–5×–4=20 C=–47=3 D=8×–3=–24 E=–8×2=–16 F=–412=8 G=–5×7=–35 H=–49=5 I=–2×–4=8 J=–6–4=–10 K=–82=–6 L=–6×3=–18
4ème3 2010-2011
Correction de l'interrogation
4–7=–3
–7,5–3,5=–11 –12–24=–36 19–51=–32
A=–57–2–9=7–5–2–9=7–16=–9
–5–7=–5–7=–12
15–9=15–9=6
8×–7=–56
10×–1,25=–12,5
–3×–11=33
1000×5,12=5120
–3×–12=36
B=–2×–5×3×–10=–300
C=–2,5×–7×4×–10×–1=700 Exercice 13 page 15
a/ –12÷3=–4 ; 15÷–3=–5 ; –45÷–9=5 b/ –50÷–10=5 ; 18÷3=6 ; –16÷4=–4 c/ 1,8÷–10=–0,18 ; 10÷4=2,5 ; –15÷–5=3
d/ –3,5÷7=–0,5 ; –40÷–0,8=50 ; 15÷5=3
Exercice : division de relatifs
–100÷10=–10
–42÷–8=5,25 –24
–4 =6
–456,2
100 =–4,562 72÷–9=–8 Exercice 15 page 15
a/ –12––4=−124=–8 ; –12–4=–12–4=–16 ;–12÷–4=3 b/ –6–10=–6–10=–16 ; –6×10=–60 ; –6÷10=–0,6 c/ –12–3=–15 ; –9÷–3=3 ; 8×–5=–40
Calcul mental
1/ –8×–9=72 2/ –6–15=–21 3/ –16÷–2=8 4/ –812=4 5/ –3––5=–35=2
6/ 9–14=–5 7/ –1–1=–2 8/ –1×1=–1 9/ –1×–2×–3=–6 10/ –34–5=–4
4ème3 2010-2011
Exercice 16 page 15 A=–8––4×7 A=–8––28
A=–828 A=20
B=–5×37 B=–157 B=–8
C=–7×2–8
C=–14–8 C=–22
D=8–6×–5
D=830 D=38
E=12––3×7 E=12––21
E=1221 E=33
F=–6–8÷–2
F=–64 F=–2
G=–35÷–73×8 G=524
G=29
H=–5×6–8÷–2
H=–304 H=–26
I=–2×–5×3–2×–4 I=10×38
I=308 I=38
J=12––385 J=12–55 J=75
J=12
Calcul mental 1/ 7×4=28 2/ –74 =-3 3/ 2–15=-13 4/ –15÷3=-5 5/ –2×–2×2=+8
6/ –8–5=-13 7/ –8×–5=+40 8/ 36
–6 =-6
9/ 1,25×1000 =1250 10/ –10÷–4=2,5 Exercice 17 page 15
a/
A=58×–26 (à faire en DM) Exercice 17 page 15
G=6×5–3×7–2×6
G=30–37–12
G=27×–5
G=–135
4ème3 2010-2011
H=9÷35×7×–42
H=35×–282
H=8×–26
H=–208
I=40–[28–3×24]
I=40–[28–64] (étape non obligatoire) I=40–28–10
I=40–18
I=40–18 I=22
Exercice 17 J page 15
J=[30–28×3]–[50–12–2×5]
J=[30–224]–[50–12–10]
J=30–26–50–2
J=4–48 ou encore J=4–48 et encore J=4–48
J=–44
J '=[34–3×7–20][–2510–2×3]
J '=[34–21–20][–2510–6]
J '=[34–1][–254] J '=33–21
J '=12