Correct Answer - Option 4 : Rs.4800
Given:
The ratio of work efficiency of P and Q = 2 ∶ 3
The ratio of work efficiency of Q and R = 4 ∶ 5
P alone can complete the work in 30 days
All three are paid Rs. 700 per day
Concepts used:
Total work done = Work efficiency × Time
Number of days an individual worked on project = Total work ÷ work efficiency
Total salary earned = Salary earned per day × Total number of working days
Calculation:
The ratio of work efficiency of P, Q and R is calculated as:
P ∶ Q = (2 ∶ 3) × 4 = 8 ∶ 12
Q∶R = (4 ∶ 5) × 3 = 12 ∶ 15
⇒ P ∶ Q ∶ R = 8 ∶ 12 ∶ 15
Work done by P = Work efficiency × Number of days
⇒ Work done by P = 8 × 30
⇒ Work done by P = 240 (Total work)
Number of days R worked on project = Total work ÷ work efficiency
⇒ 240 ÷ 15
⇒ 16 days
As salary is paid in the same ratio as the efficiency of work, that is, 8 ∶ 12 ∶ 15,
⇒ Salary earned by R per day = [15/(8+12+15)] × Rs.700
⇒ (15/35) × Rs.700
⇒ Rs.300
Total salary earned by R in 16 days = Salary earned per day × number of days work done by an individual
⇒ Rs.300 × 16
⇒ Rs. 4800.
∴ Individual R earned Rs. 4800 by working on the project for 16 days.
