Some pens are divided among P, Q, R, and S. P gets twice the number of pens that Q gets. R gets the same number of pens as S gets. If P gets 25 pens more than S and the ratio of the number of pens that Q and R get 2 : 3, then what is the number of pens that S gets?
1
55
2
65
3
75
4
85
5
None