Hi All,
Many Test Takers would use an algebraic approach to this question, which is fine. However, there are some interesting Number Property patterns that you can take advantage of - to minimize the amount of algebra that is required - and use estimation (and TESTing THE ANSWERS) to get to the solution.
To start, notice how all of the numbers in this prompt are even integers (6 walls, 204 bricks/wall, 84 total hours of work and all of the answers are even integers). This is important because we're told that Ramon lays bricks 50% FASTER than Jason does. From the answers, we know that Ramon's rate is an integer, but considering how 'nice' all of the other numbers are, it's really likely that Jason's rate is ALSO an integer. This allows us to eliminate 2 of the answers - B and D....
A: 24 is 50% greater than 16
B: 22 is 50% greater than 14.something
C: 18 is 50% greater than 12
D: 14 is 50% greater than 9.something
E: 12 is 50% greater than 8
Thus, the answer is almost certainly A, C or E.
The total number of bricks that need to be laid to complete the job is (6)(204) = 1224 bricks and we know that the pair worked a total of 84 hours... If we round both of those numbers off, we'd have 1200 bricks and 80 hours of work.
1200/80 = an average of 15 bricks/hour
Now, look at Answers A, C and E. Which is the ONLY one that gives us a potential average of 15 bricks/hour? Answer C (the average would be between 12 and 18). Answer A is too big and Answer E is too small.
Final Answer:
GMAT assassins aren't born, they're made,
Rich
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