Explanation:

- We have a sum of Rs16,200 divided among A, B, and C.

- If A received Rs1,200 less, shares are in the ratio 3:4:5.

- This ratio indicates that the respective amounts of A, B, and C (after reducing A's share by Rs1,200) form parts of a whole divided into 12 parts (3+4+5).

- Let A’s reduced share be 3x, B’s share be 4x, and C’s share be 5x.

- The equation becomes: 3x + 4x + 5x = Rs16,200 - Rs1,200.

- Solving, we get 12x = Rs15,000, hence x = Rs1,250.

- Original A's share is 3x + Rs1,200 = Rs3,750 + Rs1,200 = Rs4,950.

- Option 1 - Rs4,950 is the correct answer.

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