Réponse :
Explications étape par étape
Bonjour
Calculer :
7/9 + 5/9
= (7 + 5)/9
= 12/9
= (3 x 4)/(3 x 3)
= 4/3
7/9 x 5/9
= (7 x 5)/(9 x 9)
= 35/81
1/4 + 7/12
= (1 x 3)/(4 x 3) + 7/12
= 3/12 + 7/12
= 10/12
= (2 x 5)/(2 x 6)
= 5/6
1/4 x 7/12
= (1 x 7)/(4 x 12)
= 7/48
9/7 + 2
= 9/7 + (2 x 7)/7
= 9/7 + 14/7
= 23/7
9/7 x 2
= (9 x 2)/7
= 18/7
2/5 + 5/7
= (2 x 7)/(5 x 7) + (5 x 5)/(7 x 5)
= 14/35 + 25/35
= 39/35
2/5 x 5/7
= 5/5 x 2/7
= 2/7
