A, B, C compare their fortunes :
A says to B, "give me ₹ 700 of your money, and I shall have twice as much as you retain".
B says to C, "give me ₹ 1400, and then I shall have thrice as much as you retain.'
C says to A, "give me ₹ 420, and then I shall have five times as much as you retain."
Find the fortunes of A, B and C.