Calculez les expressions: a) 1/3 + 5/9 b) 11/6 + -7/3 c) 17/24 - -5/6 a) 2/3+1/8 b) -2/5 + 3/4 c)-5/7 - 3/2 d) 4/7 - 4/5 e) 3- 5/7 f) -2 - 3/4
Mathématiques
Evaaaa13
Question
Calculez les expressions:
a) 1/3 + 5/9
b) 11/6 + -7/3
c) 17/24 - -5/6
a) 2/3+1/8
b) -2/5 + 3/4
c)-5/7 - 3/2
d) 4/7 - 4/5
e) 3- 5/7
f) -2 - 3/4
a) 1/3 + 5/9
b) 11/6 + -7/3
c) 17/24 - -5/6
a) 2/3+1/8
b) -2/5 + 3/4
c)-5/7 - 3/2
d) 4/7 - 4/5
e) 3- 5/7
f) -2 - 3/4
1 Réponse
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1. Réponse maudmarine
Calculez les expressions :
a) 1/3 + 5/9
= 1 x 3 / 3 x 3 + 5/9
= 3/9 + 5/9
= 8/9
b) 11/6 + -7/3
= 11/6 - 7/3
= 11/6 - 7 x 2 / 3 x 2
= 11/6 - 14/6
= - 3/6
= 3 x - 1 / 3 x 2
= - 1/6
c) 17/24 - -5/6
= 17/24 + 5/6
= 17/24 + 5 x 4 / 6 x 4
= 17/24 + 20/24
= 37/24
a) 2/3+1/8
= 2 x 8 / 3 x 8 + 1 x 3 / 8 x 3
= 16/24 + 3/24
= 19/24
b) -2/5 + 3/4
= - 2 x 4 / 5 x 4 + 3 x 5 / 4 x 5
= - 8/20 + 15/20
= 7/20
c)-5/7 - 3/2
= - 5 x 2 / 7 x 2 - 3 x 7 / 2 x 7
= - 10/14 - 21/14
= - 31/14
d) 4/7 - 4/5
= 4 x 5 / 7 x 5 - 4 x 7 / 5 x 7
= 20/35 - 28/35
= - 8/35
e) 3- 5/7
= 3 x 7 / 1 x 7 - 5/7
= 21/7 - 5/7
= 16/7
f) -2 - 3/4
= - 2 x 4 / 1 x 4 - 3/4
= - 8/4 - 3/4
= - 11/4