1]If a:b = 5:9 and b:c = 4:7,find a:b:c
a] 20,30,60 b]20,36,60 c]20,30,63 d]20,36,63

a:b = 5:9
b:c = 4:7
b:c = [4* (9/4)] : [ 7*(9/4)]
      = 9: (63/4)
a:b:c = 5:9: (63/4) = 20: 36: 63

2]If a:b = 5:7 and b:c = 6:11,find a:b:c
a] 20,42,60 b]20,36,77 c]20,30,63 d]30,42,77

3]If a:b = 4:6 and b:c = 8:10,find a:b:c
a] 12,30,60 b]12,36,60 c]8,30,63 d]8,12,15

4]If a:b = 3:5 and b:c = 4:7,find a:b:c
a] 20,35,60 b]12,36,60 c]20,35,63 d]12,20,35