GMAT Problem of the Day: Drawing Conclusions on CR

This harder critical reasoning question requires us to draw our own conclusion based on information provided in the question-stem. Set a timer for 2 minutes, then dive in! Scroll down to check your work against my explanation!

At Legal Services, LLC last year, the average annual salary for attorneys was $75,000, while the average salary for paralegals was $50,000. The average annual salary for all Legal Services, LLC employees was $45,000.

If the information above is correct, which one of the following conclusions can properly be drawn on the basis of it?

A) There were twice as many attorneys at Legal Services, LLC as there were paralegals last year.
B) There were more paralegals than attorneys at Legal Services, LLC last year.
C) There were two attorneys and three paralegals at Legal Services, LLC last year.
D) There was at least one Legal Services, LLC employee who earned less than the average paralegal earned last year.
E) At least one paralegal made less than $50,000 last year.

Here’s how I broke it down:

Conclusion: Avg. annual salary for ALL employees was $45,000

Evidence: avg sal attorneys is $75,000, and avg. sal paralegals is $50,000

Assumptions: Average = Total Sum / # of terms, so the average of the attorneys and the paralegals together would be $60,000. Since the average salary is less than that, then there must be significant # of employees who are making less than $45,000.

Question Rephrase: What is TRUE based on the evidence?

Prediction: There must be some more poorly-paid employees.

The answer is (D).

(B) is incorrect because it does not HAVE to be true that there were more paralegals than attorneys. There could be the exact same number of paralegals as attorneys. What is weighting the average down to $45,000 is the fact that there is an unaccounted for number of employees making LESS than what the paralegals make.