Correct Answer - Option 3 : Rs. 980
Given:
Total contract amount = Rs. 2100
A and B can complete the work in 40 days and 24 days respectively
Calculations:
Consider, C’s 1 day’s work = 1/C
⇒ (A + B + C)’s 8 days work = 1
⇒ 8 [(1/40) + (1/24) + (1/C)] = 1
C ’s 1 day’s work 1/C = (1/8) – (1/40) – (1/24)
⇒ (15 – 3 – 5)/120 = 7/120
Ratio of working capacities = 1/40 : 1/24 : 7/120 = 3 : 5 : 7
Total (A + B + C)’s share = Rs. 2100
⇒ 15 parts = 2100
⇒ 1 part = 140
C’s share = 7 parts = 7 × 140 = Rs. 980.
∴ C's share is 980 Rs.