Shortcut Trick
Ratio of work done (A : B) = (7 days × 2 units) : (5 days × 4 units)
⇒ 14 : 20 = 7 : 10
Total units = 7 + 10 = 17 units → ₹4250
Difference = 10 − 7 = 3 units → (4250 ÷ 17) × 3
⇒ 250 × 3 = ₹750
∴ The correct answer is ₹750.
Alternate Method
Given:
Time worked by A = 7 days
Time worked by B = 5 days
Daily efficiency of A = 2 units/day
Daily efficiency of B = 4 units/day
Total wages received = ₹4250
Formula Used:
Work Done = Time × Efficiency
Individual Wage = (Work Done by Person ÷ Total Work Done) × Total Wages
Calculations:
⇒ Total work done by A = 7 × 2 = 14 units
⇒ Total work done by B = 5 × 4 = 20 units
⇒ Total work done by both = 14 + 20 = 34 units
⇒ Wage per unit of work = 4250 ÷ 34 = ₹125
⇒ Share of A = 14 × 125 = ₹1750
⇒ Share of B = 20 × 125 = ₹2500
⇒ Difference in shares = 2500 − 1750 = ₹750
∴ The correct answer is ₹750.
Additional Information
Wage Distribution Principle
Wages are always distributed in the ratio of the total work done by each individual. If the time worked is the same, wages are distributed in the ratio of efficiencies.
Efficiency and Work Relation
Total Work = Time × Efficiency. For a fixed amount of work, efficiency is inversely proportional to the time taken (E1/E2 = T2/T1).
Combined Work Formula
The total work in a project involving multiple people is the sum of the individual products of their working days and their respective daily efficiencies.