IEMCET BBA/BCA aptitude preparation: Time and work rates — worked example and reasoning

Problem to solve

One worker needs 6 hours and another 3 hours. How long together under the model?

Try the problem before reading the answer. Record the requested quantity, relevant information and any interpretation choices. Keep this original practice example separate from official examination questions or previous-year papers.

Choose the governing principle

If workers finish alone in a and b time units, combined rate is 1/a+1/b.

For constant independent rates, completed work adds. Work time is the reciprocal of rate for one complete job.

Worked answer

Rate=1/6+1/3=1/2 job/hour, so time is 2 hours.

The answer follows the stated model and the values in this question. Preserve exact expressions when given; if you use a numerical approximation, label it and keep sufficient precision until the final step.

Audit the reasoning

Return to the wording and test the proposed answer. Check the base of a percentage, the weights in an average and the units in a rate. For language tasks, verify agreement and context without adding facts the passage never supplies.

A specific error to avoid here: Adding individual completion times rather than rates reverses the cooperation calculation.

Explain before repeating

Write a short explanation linking the governing principle to the answer rather than copying the final line. Identify one assumption and explain how violating it would make this method unreliable. Use the linked worksheet for a new task, then return to this example after a delay and solve it without the answer visible.

Official sources and verification

Sources checked on 26 October 2026. A source’s date, programme and campus limit which claims it supports. Official pages may change after review.

1. UEM Kolkata — IEMCET 2026 syllabus and instructions

   Historical course-specific preparation guidance. Some introductory route text conflicts with the central portal.

2. IIT Guwahati — GATE 2026 General Aptitude syllabus

   General transferable aptitude topic reference, not an official detailed IEMCET BBA/BCA blueprint.

Found a discrepancy? Send the page and the official notice for correction.