bjr
Il manque des parenthèses
1)
28*6/7 = (28 x 6)/7 = (4 x 7 x 6)/7 (on simplifie par 7)
= 4 x 6 = 24
2)
12/75*30 = 12/(75 x 30) = (4 x 3)/ (75 x 3 x 10) (on simplifie par 3)
= 4 /(75 x 10) (on simplifie par 2)
= 2/(75 x 5)
= 2 / 375
OU
12/75*30 = (12/75) x 30 = (12 x 30)/75 (on simplifie par 3)
= (4 x 30) / 25 (on simplifie par 5)
= (4 x 6)/ 5
= 24/5 (ou 4,8)
= (4 x 2)/3 (on simplifie par 5)
3)
9/14*7 = 9 /(14 x 7) = 9/98
OU
9/14*7 = (9/14) x 7 = (9 x 7)/14
= (9 x 7)/(2 x 7) (on simplifie par 7)
= 9/2 (ou 4,5)
