Work and Time
Work and Time Data Sufficiency problems test your ability to determine if given statements provide enough information to find time to complete work, individual rates, or combined efficiency. You must assess sufficiency using the work rate formula: Work = Rate × Time.
What You'll Learn
Introduction to Work and Time
Work and Time Data Sufficiency problems test your ability to determine if given statements provide enough information to find time to complete work, individual rates, or combined efficiency. You must assess sufficiency using the work rate formula: Work = Rate × Time.
Prerequisites
How to Solve Work and Time Problems
Step 1: Identify what is being asked (time for A alone, time together, etc.)
Step 2: Translate each statement into rate equations
Step 3: Check if Statement (1) alone gives a unique answer
Step 4: Check if Statement (2) alone gives a unique answer
Step 5: Combine statements if needed
Step 6: Remember: 1/A + 1/B = 1/T_combined
Step 7: Select the appropriate DS answer choice
Example Problem
Example: How many days will A take to complete the work alone? Statement (1): A and B together complete the work in 6 days. Statement (2): B alone completes the work in 10 days. Solution: Step 1: Question asks for A's time alone Step 2: Statement (1): 1/A + 1/B = 1/6 (one equation, two unknowns) → NOT sufficient alone Step 3: Statement (2): B = 10 days (one value, but A unknown) → NOT sufficient alone Step 4: Together: 1/A + 1/10 = 1/6 → 1/A = 1/6 - 1/10 = (5-3)/30 = 2/30 = 1/15 → A = 15 days → SUFFICIENT together Answer: Both statements together are sufficient
Pro Tips & Tricks
- Combined time alone (without individual rates) → insufficient for individual times
- Individual time alone → sufficient for that person's rate
- Two individual times → sufficient for combined time
- One individual time + combined time → sufficient for the other individual time
- Work completed in a certain time gives rate information
- Fraction of work done by each can provide rate ratios
Shortcut Methods to Solve Faster
Common Mistakes to Avoid
Practice Worksheets
Practice makes perfect! Work through these worksheets to master Work and Time. Each worksheet contains 20 questions with detailed explanations. Start from Worksheet 1 and progress through increasing difficulty levels.
Exam Importance
Work and Time is an important topic for various competitive exams. Here's how frequently it appears:
Ready to Master Work and Time?
Start with Worksheet 1 and work your way up to expert level! Each worksheet includes: