Bsr,j'ai un exercice en maths sur le calcul numérique
Opérations en écriture fractionnaire

Exercice 1:
Calculer et donner le résultat sous la forme la plus simple possible:(/=sur)

1) A=3 sur 5 + 4sur 5=
B=7/11-4/11=
C=3/13-8/13=
D=3/2+-7/2=

2)A=1/3-5/9=
B=-7/12+3/4=
C=4/7-5/21=
D=-3/35-3/7=

3)A=3/4+2/5=
B=-2/5+1/3=
C=5/4+-7/6=
D=4/-9-5/6=

4)A=1+1/5=
B=2/3-1=
C=-3/4-3=
D=-6-2/7=

1

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Meilleure réponse !
2014-09-06T19:10:46+02:00
Exercice 1:
Calculer et donner le résultat sous la forme la plus simple possible:

1)
A = 3/ 5 + 4/ 5
A = 7/5

B = 7/11 - 4/11
B = 3/11

C = 3/13 - 8/13
C = - 5/13

D = 3/2 + - 7/2
D = 3/2 - 7/2
D = - 4/2
D = 2 x - 2 / 2 x 1
D = - 2/1
D = - 2

2)
A = 1/3 - 5/9
A = 1 x 3 / 3 x 3 - 5/9
A = 3/9 - 5/9
A = - 4/9

B = - 7/12 + 3/4
B = - 7/12 + 3 x 3 / 4 x 3
B = - 7/12 + 9/12
B = 2/12
B = 2 x 1 / 2 x 6
B = 1/6

C = 4/7 - 5/21
C = 4 x 3 / 7 x 3 - 5/21
C = 12/21  -  5/21
C = 7/21
C = 7 x 1 / 7 x 3
C = 1/3

D = -3/35 - 3/7
D = - 3/35 - 3 x 5 / 7 x 5
D = - 3/35 - 15/35
D = - 18/35

3)
A = 3/4 + 2/5
A = 3 x 5 / 4 x 5 + 2 x 4 / 5 x 4
A = 15/20 + 8/20
A = 23/20

B = - 2/5 + 1/3
B = - 2 x 3 / 5 x 3 + 1 x 5 / 3 x 5
B = - 6/15 + 5/15
B = - 1/15

C = 5/4 + - 7/6
C = 5/4 - 7/6
C = 5 x 6 / 4 x 6 - 7 x 4 / 6 x 4
C = 30/24 - 28/24
C = 12/24
C = 12 x 1 / 12 x 2
C = 1/2

D = 4/-9 - 5/6
D = 4 x 2 / - 9 x 2 - 5 x 3 / 6 x 3
D = - 8/18 - 15/18
D = - 23/18

4)
A = 1 + 1/5
A = 1 x 5 / 1 x 5 + 1/5
A = 5/5 + 1/5
A = 6/5

B = 2/3 - 1
B = 2/3 - 1 x 3 / 1 x 3
B= 2/3 - 3/3
B = - 1/3

C = - 3/4 - 3
C = - 3/4 - 3 x 4 / 1 x 4
C = - 3/4 - 12/4
C = - 15/4

D = - 6 - 2/7
D =
- 6 x 7 / 1 x 7 - 2/7
D = - 42/7 - 2/7
D = - 49/7
D = 7 x - 7 /7 x 1
D = - 7/1
D = - 7