Exos - Calculs sur les fractions

Feuille d’exercices – Calculs sur les fractions – 5ème
Exercice I : Simplifier le plus possible
28
=
12
34
=
22
25
=
45
35
=
63
24
=
20
38
=
42
15
=
12
25
=
100
55
=
33
26
=
39
60
=
44
200
=
70
18
=
54
56
=
40
27
=
15
31
=
93
57
=
19
46
=
74
91
=
52
95
=
76
Exercice II : Calculer
Exercice III : Calculer
2 9
+ =
7 7
2 8
+ =
9 9
18 11
− =
5 5
12 1
−
=
19 19
5 9
+ =
16 4
7 5
+ =
32 8
38 11
−
=
5 25
2 7
−
=
3 18
12 11
+
=
5 20
13 3
+ =
64 8
47 5
− =
54 9
6 13
−
=
7 21
17 5
+ =
36 9
9 2
+ =
40 5
37 2
− =
45 5
53 6
− =
42 7
Exercice IV : Calculer et simplifier (il faut souvent mieux simplifier AVANT de calculer, quand c’est possible)
2 9
× =
7 5
12 4
× =
9 7
1 25
×
=
10 3
16 3
× =
19 8
24 5
× =
11 6
13 6
×
=
8 26
36 2
×
=
5 18
52 4
×
=
4 48
2 10 9
× × =
5 6 7
1 3 5 7
× × × =
3 5 7 9
4 6
× =
15 8
11 25 8 3
×
×
× =
12 14 22 5
Exercice V : Calculer, en suivant les priorités
1 5 1
+ × =
2 3 4
2 3 3 1
+
− × =
5 10 4 5
1 
3 5   3
 + × +
=
 7 14   11 22 
13  5 3 1 
−
+ ×
=
4  8 2 8 
6 14 3
×
+ =
7 24 2