Ten years ago, the ratio of ages of P and Q was 3:2. Ten years from now, the ratio of their ages will be 7:6. What is P's age at present? Choose one.
A) 18	B) 20	C) 21	D) 24	E) 25
2(P-10)/3 = (Q-10). Then Q = 2(P-10)/3 + 10   6(P+10)/7 = Q+10   6(P+10)/7 = 2(P-10)/3 + 20   18P+180 = 14P + 280   4P = 100   P = 25   The answer is 25.
<result>E</result>
Ten years ago, the ratio of ages of P and Q was 3:2. Ten years from now, the ratio of their ages will be 7:6. What is P's age at present?