salut aider moi slv simplifiez auparavant s'il y a lieu puis réduire au même dénominateur les fractions suivantes 21/35= 17/42= et 21/63= e) 1/2= 2/3= 3/4= et 5

Bonsoir

simplifiez auparavant s'il y a lieu puis réduire au même dénominateur les fractions suivantes

21/35= (7 x 3)/(7 x 5) = 3/5

17/42
21/63= 21/(3 x 21) = 1/3

3/5 = (3 x 42)/(5 x 42) = 126/210

17/42 = (17 x 5)/(42 x 5) = 85/210

1/3 = (1 x 5 x 14)/(3 x 5 x 14) = 70/210

e) 1/2= (1 x 3 x 8)/(2 x 3 x 8) = 24/48

2/3= (2 x 16)/(3 x 16) = 32/48
3/4= (3 x 3 x 4)/(4 x 3 x 4) = 36/48
5/16= (5 x 3)/(16 x 3) = 15/48

f) 2/3= (2 x 3 x 16)/(3 x 3 x 16) = 96/144

4/9= (4 x 16)/(9 x 16) = 64/144
11/12= (11 x 3 x 4)/(12 x 3 x 4) = 132/144
15 /16= (15 x 9)/(16 x 9) = 135/144

g)5=

32/56 = (8 x 4)/(8 x 7) = 4/7

9

5 = (5 x 7)/7 = 35/7

9 = (9 x 7)/7 = 63/7

h)7;=

18/36 = 18/(2 x 18) = 1/2

9/13=

7 = (7 x 13 x 2)/(2 x 13) = 182/26

1/2 = (1 x 13)/(2 x 13) = 13/26

9/13 = (9 x 2)/(13 x 2) = 18/26

i)15/25 = (5 x 3)/(5 x 5) = 3/5

14/49= (2 x 7)/(7 x 7) = 2/7
4=
4/11=

3/5 = (3 x 7 x 11)/(5 x 7 x 11) = 231/385

2/7 = (2 x 5 x 11)/(7 x 5 x 11) = 110/385

4 = (4 x 385)/385 = 1540/385

4/11 = (4 x 5 x 7)/(11 x 5 x 7) = 140/385

j) 3/4

4/6 = (2 x 2)/(3 x 2) = 2/3

6/18= 6/(3 x 6) = 1/3
1/3= 

3/4 = (3 x 3)/(4 x 3) = 9/12

2/3 = (2 x 4)/(3 x 4) = 8/12

1/3 = (1 x 4)/(3 x 4) = 4/12