PS500 TEST23 #17

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PS500 TEST23 #17

by dunkin77 » Tue Apr 17, 2007 10:29 am
Hi,

I though C=1 and B=8, however, the correct answer is B).
Can anyone please explain?
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by Cybermusings » Tue Apr 17, 2007 11:24 am
1/b = b/c = c/8


1/b = b/c
Or b^2=c

b/c=c/8
or 8b=c^2
(Now substituting value of c from the first equation; wherein c = b^2)
8b=c^2
or 8b = b^2*b^2
or 8 = b^3
Thus b = 2(b can only be positive)

Now 1/b=b/c
or 1/2=2/c
Thus c = 4

Hence b+c = 2+4 = 6
Hence Choice B

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by ns88 » Tue Apr 17, 2007 2:23 pm
if 1/b=b/c=c/8

then 1/b +c/8 = 2* (1/b)

8+cb=16

cb=8

what two factors of 8 ....check the answer choices?

4+2= 6