Bonjour
A= 3/4+ 6/3
A = (3 x 3) / (4 x 3) + (6 x 4) / (3 x 4)
A = 9/12 + 24/12
A = 33/12
A = (3 x 11) / (3 x 4)
A = 11/4
B=16/35 × 25/24
B = 400/840
B = (40 x 10) / (40 x 21)
B = 10/21
C= 16/12 : 20/14
C = 16/12 x 14/20
C = 224/240
C = (16 x 14) / (16 x 15)
C = 14/15.