A sum of Rs.4680 is divided amongst P, Q, R and S such that the ratio of shares of P and Q is 2 ∶ 3, that of Q and R is 4 ∶ 5 and that of R and S is 1 ∶ 2. What is the difference between the shares of R and S?
1
Rs. 1080
2
Rs. 1270
3
Rs. 960
4
Rs. 1320