GMAT Practice Question - Work Time

Concept: Word Problem in Work and Time. Framing equations for different rates of work.

This GMAT quant question is a word problem in work and time. Concept: framing equations and solving when two people with different efficiencies (rate at which they work) work together to complete a task.

Question: Ram, who is half as efficient as Krish, will take 24 days to complete a task if he worked alone. If Ram and Krish worked together, how long will they take to complete the task?

  1. 16 days
  2. 12 days
  3. 8 days
  4. 6 days
  5. 18 days

Explanatory Answer

Video explanation provided for this question

Ram takes 24 days to complete the task, if he works alone.
Krish is twice as efficient as Ram is. So, working alone, Krish will take half the time to complete the task.i.e., 12 days.

Ram will complete \\frac{1}{24}\\)th of the task in a day.
Krish will complete \\frac{1}{12}\\)th of the task in a day.

When they work together, they will complete \\frac{1}{24} + \frac{1}{12} = \frac{1}{8}\\)th of the task in a day.
Therefore, when they work together they will complete the task in 8 days.

Choice C is the correct answer.

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