500 ps test26 #17

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500 ps test26 #17

by dunkin77 » Thu Apr 19, 2007 10:25 am
Hi,

I thought the answer was B) but the correct answer is C) -- Can anyone show me..? :oops:
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by Neo2000 » Thu Apr 19, 2007 6:18 pm
Work your way from the right hand side

1/(2^12) + 1/(2^12) = 2/(2^12) = 1/2^11

1/2^11+ 1/2^11 = 2/2^11 = 1/2^10

1/2^10 + 1/2^10 = 1/2^9

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by zaffar » Thu Apr 19, 2007 11:29 pm
1/(2^10) + 1/(2^11)+1/(2^12) + 1/(2^12)
=1/(2^10) [1+1/2+1/4+1/4]
=1/(2^10) [4+2+1+1/4]
=1/(2^10) [8/4]
=1/(2^10) 2
=1/(2^9)

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by rajeshvellanki » Sat Apr 21, 2007 3:33 pm
best way is to take the HCF:

2^2/2^12 + 2/2^12 + 2/2^12 =8/2^12= 2^3/2^12= 1/@^9

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by Cybermusings » Sun Apr 22, 2007 4:25 am
(1/2^10)+(1/2^11)+(1/2^12)+(1/2^12)
The LCM here would be 2^12
So it would become (2^2+2+1+1)/2^12
=8/2^12
=2^3/2^12
=1/2^9