A's rate: 1 job in 1 day = 1 job/day. B's rate: 1 job in 2/5 days = 5/2 = 2.5 jobs/day. Working together for 1/5 day: (1 + 2.5) × 1/5 = 3.5/5 = 7/25 of job done. Remaining: 18/25. C completes this in 6 hours. Given 20 hours = 1 day, 6 hours = 6/20 = 0.3 day. C's rate = (18/25)/0.3 = 18/7.5 = 12/5 = 2.4 jobs/day. C's share of work = 18/25 of total. Payment: (18/25) × 734.50 = 18 × 29.38 = 528.84. But option B is 220.35. Let me recalculate... 734.50 × 18/25 = 734.50 × 0.72 = 528.84. This doesn't match. Perhaps 20 hours = 1 day means work rate is calculated in days: C took 6/20 = 0.3 days to do 18/25 work, so C's daily rate = (18/25)/0.3 = 2.4. If A, B, C all worked together for 1/5 day at their respective rates (1, 2.5, 2.4), total work = (1 + 2.5 + 2.4) × 0.2 = 5.9 × 0.2 = 1.18 jobs... But job should be complete. There's inconsistency. Let me reconsider: C completes remaining alone in 6 hours. If 20 hours = 1 day, then 6 hours = 0.3 days. C's contribution: remaining work done in 0.3 days alone. Total payment = Rs. 734.50. A and B worked 1/5 day each. C worked 0.3 day = 3/10 day. If payment is proportional to work done at their rates: A's work = 1 × 1/5 = 1/5. B's work = 2.5 × 1/5 = 1/2. C's work = ? × 3/10. Total work = 1. So C's work = 1 - 1/5 - 1/2 = 1 - 0.2 - 0.5 = 0.3 = 3/10. So C's rate = (3/10)/(3/10) = 1 job/day. Payment share: C did 3/10 of work, so gets (3/10) × 734.50 = 220.35. This matches option B.