A person X can do a piece of work worth ₹3000 in 6 days. But he engages an…
2023
A person X can do a piece of work worth ₹3000 in 6 days. But he engages an assistant Y, and completes the work in 4 days. Find the share of the assistant Y in completing the work.
Answer: B. ₹1000 — ConceptWork rate is the fraction of a job completed per unit time. When two people work together, their rates add, so an assistant’s rate equals the combined…
- A.
₹800
- B.
₹1000
- C.
₹1500
- D.
₹1200
Show answer & explanation
Correct answer: B
Concept
Work rate is the fraction of a job completed per unit time.
When two people work together, their rates add, so an assistant’s rate equals the combined rate minus the first person’s rate. Payment for the same job is divided in proportion to each person’s contribution.
Application
X’s rate is 1/6 of the job per day.
The combined rate of X and Y is 1/4 of the job per day.
Therefore, Y’s rate is 1/4 − 1/6 = (3 − 2)/12 = 1/12 of the job per day.
In 4 days, Y completes 4 × 1/12 = 1/3 of the job.
Y’s share is ₹3000 × 1/3 = ₹1000.
Cross-check
In 4 days, X completes 4 × 1/6 = 2/3 of the job. The contributions 2/3 + 1/3 equal the whole job, and the corresponding shares ₹2000 + ₹1000 equal ₹3000.
Result
The assistant Y’s share is ₹1000.