Hi All,
This question can be solved by TESTing THE ANSWERS. There is also a logical 'shortcut' in this prompt that can help you to avoid a lot of 'math work.'
We're told that 3 business people are each going to pay one third of a total investment in a company. We're also told that each of them would pay $7,200 LESS if they could find two more equal investors. We're asked for the TOTAL investment in the new business.
Since the original 3 investors would each pay $7200 LESS than they would originally pay, then each is clearly paying MORE than $7200 right now. That means the total investment must be GREATER than (3)($7200) = $21,600. This narrows down the options to Answers A and B.
Another thing to consider is that since the 3 original investors were all going to pay the SAME amount, the total investment IS almost certainly going to be a multiple of 3. Only Answer B matches, but you can still prove that it's the correct answer with a little work.
$54,000 spread among 3 investors = $18,000 each
$54,000 spread among 5 investors = $10,800 each
Difference = $18,000 - $10,800 = $7,200
This is an exact MATCH for what we were told, so this MUST be the answer.
Final Answer:
GMAT assassins aren't born, they're made,
Rich