Bonjour,
Ecrire les expressions suivantes sous forme fractionnaire la plus simple possible :
2/3 - 5/3 x (1 -1/5)
= 2/3 - 5/3 x [(1 x 5) / (1 x 5) - 1/5]
= 2/3 - 5/3 x (5/5 - 1/5)
= 2/3 - 5/3 x 4/5
= (2 x 5) / (3 x 5) - 20/15
= 10/15 - 20/15
= - 10/15
= (5 x - 2) / (5 x 3)
= - 2/3.
