Réponse :
bonjour
A = (3 - 2/3 ) : ( 4/3 x 7 )
A = ( 9/3 - 2 /3 ) : 28/3
A = 7/3 : 28/3
A = 7/3 x 3/28
A = 21/84 = 1/4
B = ( 2/3 : 5/6 ) - 2/5
B = ( 2/3 * 6/5 ) - 2/5
B = 12/15 - 2/5
B = 12/15 - 6/15
B = 6/15 = 2/5
C = ( -3/4 + 1/2 ) : ( 2/5 - 5/2 )
C = ( -3/4 + 2/4 ) : ( 4/10 - 25/10 )
C = - 1/4 : - 21/10
C = - 1/4 x - 10/21
C = 1/84
Explications étape par étape :
