A can do 20% part of a work in 8 days, B works 30% part of the same work in 12 days and C works 40% part of that work in 18 days. If B and C's 1-day wage difference is Rs 12, then what will be the wage of A on working 35 days?

A does 20% work in 8 days → A's 1 day work = 20%/8 = 2.5%. B does 30% in 12 days → B's 1 day work = 30%/12 = 2.5%. C does 40% in 18 days → C's 1 day work = 40%/18 ≈ 2.22%. B and C work ratio is 2.5:2.22. B-C wage difference = Rs 12 for 1 day. A's wage for 35 days = (A's work/B's work) × (B's wage - C's wage) × 35 = (2.5/2.5) × 12 × 35 = Rs 3780.