Scaling identical work: Aarti completes one job in 6 days. In how many days will she complete three jobs of the same type (assuming identical size and rate)?

Introduction / Context:
When identical jobs are repeated and the worker’s rate remains constant, total time scales linearly with the number of jobs. Here, “three jobs” means three times the original amount of work at the same pace.

Given Data / Assumptions:

• Aarti’s time per job = 6 days.
• Number of identical jobs = 3.
• Rate is constant; no setup or downtime is introduced.

Concept / Approach:
Total time for k identical jobs at the same rate = k * (time for one job). Thus, multiply the single-job duration by 3.

Step-by-Step Solution:
Time for 1 job = 6 days. Time for 3 jobs = 3 * 6 = 18 days.

Verification / Alternative check:
Rate-based view: Aarti’s rate = 1/6 job/day. To complete 3 jobs, needed days = 3 / (1/6) = 18 days.

Why Other Options Are Wrong:
21 days assumes slower rate; 3 and 6 days ignore the scaling by three.

Common Pitfalls:
Confusing “three times the work” with “three workers.” The scenario keeps the same worker and rate, so time multiplies by 3.

Final Answer:
18 days