A person invested Rs.(P + 700) in scheme A at 12% SI per annum for 15 years and the amount obtained is Rs.(4P-200). If Rs. (M + 300) is invested at the same scheme at the same rate for 10 years then the interest obtained is Rs.(3P + 1200).

Which of the following statement/s is/are true?

I. P = 2M

II: P + M = 2 (M - 450)

III: HCF of P and M is 200.