Bonsoir
3)
a.
A = 17/8 = 34/16
B = 8/4 = 32/16
b.
31/100 = 310/1 000
4/10 = 400/1 000
4)
A = 2/3 = 4/6
B = 3/2 = 9/6
A = 7/6 = 35/30
B = 7/10 = 21/30.