GMAT Prep / Percents

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by muzali » Tue Dec 02, 2008 5:14 pm
2 ways to solve:

1. The quick way
70% of 800 employees = 0.7*80 = 560
[(560-y)/(800-y)]*100 should equal 60.
Start plugging the answer choices:
y=200 gives (360/600)*100 which is what we want, so answer is A

2. The longer way
70% of 800 employees = 0.7*80 = 560
So (560-y) = (60/100)*(800-y)
5600 - 10 y = 4800 - 6y
4y = 800, so y = 200, same answer as the 1st way.