Is Zero midway S & -S ?

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Is Zero midway S & -S ?

by nisagl750 » Mon Nov 12, 2012 10:41 pm
Image




IMOB

OAC


can anyone explain?

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by eaakbari » Tue Nov 13, 2012 7:29 am
Answer is C

Info : r,s,t are real numbers whose sign is unknown, is zero halfway between r & s implying is r =- s ?

Statement (I)
s is right of zero
meaning s &b t are positive. Insuff

Statement (II)
Distance between t & r is same as distance between t & -s
This gives rise to 2 cases

1) r = -s
2) There is a number -s on the right hand side of t on the number-line which is equidistant from r. ( Visualize using r = -3, s=-2, t=-1 & -s = 1)

Hence Insuff


(I) &(II) together,

Since statement (I) conflicts with case 2 of (II), this leaves only case 1 which implies r=-s and zero lies between them.

Hence Suff

Answer - C
Last edited by eaakbari on Tue Nov 13, 2012 12:42 pm, edited 1 time in total.
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by prat_agl » Tue Nov 13, 2012 12:40 pm
eaakbari wrote:Answer is C

2) There is a number -s on the right hand side of t on the number-line which is equidistant from r. ( Visualize using r = -3, s=-2, t=1 & -s = 1)

Hence Insuff

But if distance between t and r is 4 and distance between t and -s is 1...which is voilating statement 2.

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by eaakbari » Tue Nov 13, 2012 12:43 pm
prat_agl wrote:
eaakbari wrote:Answer is C

2) There is a number -s on the right hand side of t on the number-line which is equidistant from r. ( Visualize using r = -3, s=-2, t=1 & -s = 1)

Hence Insuff

But if distance between t and r is 4 and distance between t and -s is 1...which is voilating statement 2.
It was a typo, I meant t=-1. Have edited the statement.

Thanks
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by prat_agl » Tue Nov 13, 2012 12:54 pm
Thanks!

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by nisagl750 » Tue Nov 13, 2012 9:11 pm
eaakbari wrote: 2) There is a number -s on the right hand side of t on the number-line which is equidistant from r. ( Visualize using r = -3, s=-2, t=-1 & -s = 1)
Missed this....

thanks