Bonjour,
Calculer:
(3/7) - (1/4) + 1= (3x4 -1x7+ 1x28)/ (7x4)= (12 - 7 + 28)/ 28= 33/28
(27/11) - (3/121) + 3= (27x11 - 3 + 3x121) / 121= (297 - 3 + 363)/ 121= 657/ 121.
(-1/7)+(1/6)-(6/7)= (-1-6)/7+1/6= (-7/7)+(1/6)= -1+(1/6)= (-1x6 +1)/6= (-6+1)/6= -5/6
