Réponses

2013-05-27T19:07:21+02:00

Bonsoir

 

A + B

= 5/3 +10/21

= 35/21 +10/21 = 45/21 = 15/7

 

A - B

= 5/3 - 10/21 = 35/21 - 10/21 = 25/21

 

A x B

=5/3 x 10/21 = 50/63

 

A = 3/8 x (4/9 +2/3)

A = 3/8 x (4/9 +6/9)

A = 3/8 x 10/9

A = 30/72 = 15/36

 

B = 7/5 x 3/10 +1/5

B = 21/50 + 1/5

B = 21/50 + 10/50

B = 31/50

  • Utilisateur Brainly
2013-05-27T19:10:13+02:00

exo 1

 

 

A+B =5/3 +10/21

       = 15/17*

 

A-B = 5/3 + 10/21

A-B = 25/21

 

si j'ai bien compris ;)

 

exo2

 

A= 3/8 x (4/9+2/3)

A= 3/8 x 10/9

A= 5/12 

 

B= 7/5 x 3/10 + 1/5

B= 21/50 + 1/5

B= 31/50

 

 voila ;)