A gold smith has five gold rings each having different weight
Statement - 1 Ring A is weighing twice as much as ring B
Statement - 2 Ring B is weighing four times as much as ring C
Statement - 3 Ring C is weighing half as much as ring D
Statement - 4 Ring D is weighing one third much as ring E
Which of the pairs of rings have ratio 1 : 2 in respect of their weights