Time and Work
Time and Work is a key topic in quantitative aptitude that deals with efficiency, work rate, and time taken to complete tasks. It is widely used in competitive exams like banking, SSC, CMAT, and placement tests.
Fundamental Principles
Work
The total task to be completed, usually taken as 1 unit.
Time
The duration required to complete the work.
Efficiency
The amount of work done per unit time.
Work Formula
Work = Efficiency × Time.
Essential Formulation Tips
- Assume total work as LCM of given times.
- Convert all work into units for easier calculation.
- Use efficiency concept instead of direct formulas.
- If A takes x days, then 1 day work = 1/x.
Shortcut Execution Techniques
- If A takes x days and B takes y days → together: (xy)/(x+y).
- Efficiency ratio is inverse of time ratio.
- Use LCM method to simplify calculations.
- If a person leaves, subtract their work rate.
Contextual Inquiries (FAQs)
Q: What is the fastest method to solve time and work questions?
A:
Q: What are the most important types of questions?
A:
Example Breakdown: Basic Work Example
Basic concept.Total work = 1 unit.
Work per day = 1/10.
Final Answer: 1/10 work per day.
Example Breakdown: Combined Work Example
Most common exam question.A's work/day = 1/10.
B's work/day = 1/15.
Combined work/day = 1/10 + 1/15.
LCM = 30 → (3 + 2)/30 = 5/30 = 1/6.
Total time = 6 days.
Final Answer: 6 days.
Example Breakdown: Efficiency Example
Shortcut-based question.Efficiency ratio A:B = 2:1.
Time ratio = 1:2.
A's time = 12/2 = 6 days.
Final Answer: 6 days.
Time & Work Practice Questions
Solve important time and work questions for banking, SSC, CMAT, and placement exams.
Q1. A can complete work in 12 days, B in 6 days. How long together?
Q2. If A does 1/5 work in a day, how many days to complete full work?
Q3. A takes 8 days, B takes 16 days. Ratio of efficiency?