If all variables are positive, is (w/x) > (y/z)?
1) w = y + 50
2) x = z + 50
1) and 2) alone are INS.
(y+50)/(z+50) > y/z
yz +50z > yz +50y
50y > 50z
y > z
Both together are INSUFICIENT so E)
My question is, however: The first time that I worked it out, I simply did this...
If w = y + 50 , then w > y
If x = z + 50 , then x > z
Divide equations by each other:
(w > y) ÷ (x > z) = (w/x) > (x/z)
Why isn't this right?
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First off, I'm not sure about your last step, as you seem to have x in there twice.
Regardless, consider this:
w = 53, y = 3, x = 54, z = 4
53/3 > 54/4 --> that's true.
Now if you replace the latter two with x = 52 and z = 2, the above no longer holds true.
Let me know if i misunderstood.
Regardless, consider this:
w = 53, y = 3, x = 54, z = 4
53/3 > 54/4 --> that's true.
Now if you replace the latter two with x = 52 and z = 2, the above no longer holds true.
Let me know if i misunderstood.