a) 12/20 x 2= 24/40
12/20 x 3= 36/50
a)12/20 : 2 = 6/10
12/20 : 4 = 3/5
b)6/18 x 2 = 12/36
6/18 x 3 = 18/45
b)6/18 : 2 = 3/9
6/18 : 3 = 2/6
c)10/30 x 2= 20/60
10/30 x 3 = 30/90
c)10/30 : 2 = 5/15
10/30 : 5 = 2/6
d)14/42 x 2 = 28/84
14/42 x 3 = 42/126
d)14/42 : 2 = 7/24
14/42 : 7 = 2/6