Two partners, Amit and Ben, initiated a business with investments of Rs. 'P + 10' and Rs. 'P,' respectively. After 'm' months, Chetan joined them with an investment equal to half of Amit's investment. If the profit shares of Amit, Ben, and Chetan after '2m' months in the partnership are in the ratio 3A: 2P: 2Q, then what is the value of P?
I. (8Q/3)
II. (3m + 2)/2
III. 2(P + 10)/3