Réponse :
Bonjour
Explications étape par étape :
A= (9/15 + 3/10) ÷ 6/5
A = (9/15 X 10/10 + 3/10 X 15/15) : 6/5
A = (90/150 + 45/150) : 6/5
A = 135/150 X 5/6
A = 675/900 = 135 /180 = 27/36 = 9/12
B = (4/5 + 7/10) ÷ (5/6 - 5/8)
B = ( 4/5 X 2/2 + 7/10) : ( 5/6 X 8/8 - 5/8 X 6/6)
B = (8/10 + 7/10) : (40/48 - 30/48)
B = 15/10 : 10/48
B = 15/10 X 48/10
B = 720/ 100 = 72/10 = 36/5
C= 12/7 - 4/7 X 35/12
C = 12/7 -140/84
C = 12/7 X 12/12 - 140/84
C = 144/84 - 140/84 = 4/84 = 1/21
D= 6/5 + 21/5 ÷ 14/15
D = 6/5 + 21/5 X 14/15
D = 6/5 +294/75
D = 6/5 X 15/15 + 294/75
D = 90/ 75 + 294/75 = 384/75 = 128/25
