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Two questions, pls help explain

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Two questions, pls help explain

by tracyyahoo » Wed Oct 05, 2011 6:11 am
(1) oes the decimal equivalent of P/Q, where P and Q are positive integers, contain only
a finite number of nonzero digits?
(1) P>Q
(2) Q=8


I chose B, why the hell is E


(2)if x^2+y^2=1, is x+y=1?

(1)xy=0
(2)y=0

I chose D, why the hell is E again,

can some one explain me????
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Source: — Data Sufficiency |
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by sl750 » Wed Oct 05, 2011 9:59 am
B looks good in problem 1. I don't know why the hell it is E

For problem 2

X^2+Y^2 = 1 can be written as (X+Y)^2 -2XY = 1

Statement 1
XY=0, that gives us two values for X+Y = -1 or 1. Insufficient

Statement 2
Y=0, that gives us two values for X = -1 or 1. Therefore two solutions for X+Y. Insufficient

Statement 1 and 2
Insufficient, as we have two solutions for X+Y
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by VivianKerr » Fri Oct 07, 2011 7:01 am
If there is a PRIME number other than 2 of 5 in the denominator of a fraction, then it will be a non-finite decimal (for example 1/3 = .333333).

We need to know what P/Q reduces to in order to answer.

1) INSUFFICIENT. If P = 2 and Q = 1, then we get 2/1 = 2, or if P = 4 and Q = 3, we get 4/3 = 1.3333, then the answer is no.

2) SUFFICIENT. The answer is B, IMO.

Check out older threads on this Q: https://www.beatthegmat.com/set24-q-26-p ... 71622.html
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