Explanation:

- Step 1: Determine individual work rates.

- A finishes in 8 days, rate = 1/8 work/day.

- B finishes in 10 days, rate = 1/10 work/day.

- C finishes in 12 days, rate = 1/12 work/day.

- Step 2: Calculate combined work rate.

- Combined rate = 1/8 + 1/10 + 1/12.

- Find a common denominator and sum these rates = 37/120 work/day.

- Step 3: Find individual shares based on work contribution.

- Total work = 1 (as the work is completed).

- Share of B = (B's rate / Combined rate) = (1/10) / (37/120) = 12/37 of the work.

- Step 4: Calculate B's share of the payment.

- Total payment = 5550.

- B's share = 12/37 × 5550 = 1800.

- Option 3: 1800 is the correct choice.

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