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Source: — Data Sufficiency |
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by tpr-becky » Tue Mar 06, 2012 2:07 pm
To get the area of the big circle we need the value for R.

Statement 1 doesn't contain any values so it will not be sufficient. BCE are left

statement 2 tells us that 75 = (R-r)(R+r) - which means that 75 = R^2 - r^2 but we don't have any relationship between R and r so we can't figure out what the nubmers would be (R and r do not have to be integers)

Together we have the equation from statement 2 and the relationship between r and R so we can solve (incidentally R = 10 and r = 5)
Becky
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