4ème9 2010-2011
Exercices sur le chapitre n°1 Exercices sur le chapitre n°1
Exercices 4 (n°3 page 14) a/
A=–1×8=-8 C=–4×–1=+4 E=1×–3=-3
B=–1×–6=+6 D=7×1=+7 F=–1×–2=+2 b/
G=–7×100=-700 I=10×–5=-50 K=1000×4=4000
H=12×–100=-1200 J=–10×–8=+80 L=–1000×–5=5000 c/
M=–3×–6=+18 O=–7×3=-21 Q=8×–4=-32
N=2×–8=-16 P=2×0=0 R=–3×9=-27 Exercices 5 (n°5 p 14)
a/
A=–7–8=–15 B=–5×–4=20 C=–47=3 D=8×–3=–24 b/
E=–8×2=–16 F=–412=8 G=–5×7=–35 H=–49=5 c/
I=–2×–4=8 J=–6–4=–10 K=–82=–6 L=–6×3=–18
4ème9 2010-2011
Exercice 6 : n°10 page 14 A=–2×5×–3=30 A=–10×–3
A=30
B=–4×–2×–3=–24 C=5×–1×–3
C=15
D=4×2×7
D=56
Exercice 7 : n°11 page 14 A=–3×–2×–10×2 A=–120
B=–3–2–102 B=–152
B=–13
C=–4×2×–1×3
C=24
D=–42–13
D=–55
D=0
E=–3×–2×–2×5×3
E=–180
F=–3–2–253
F=–78
F=+1
Exercice 7 : calcul mental
1/ 8×7
2/ –2×–5
3/ –1–1 4/ –2×9 5/ 7,51×10
6/ –1×–1×–1×–1
7/ –1–1–1–1
8/ 9×8 9/ 3,57,5 10/ 0×1=0
4ème9 2010-2011
Exercice 8 (n°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÷3=5 Exercice 9
–33 –11=3
–24÷3=–8 36÷–6=–6
–1
2=–0,5 42÷–7=–6
–56÷8=–7 10÷–4=–2,5
–12,5
–10 =1,25 –64÷8=–8 0÷–50=0
Exercices 10 (n°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
Exercice 17 page 15 G=6×5–3×7–2×6 G=30–3×7–12
G=27×–5
G=–135