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DS- OG Quantitative Review #96, help

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DS- OG Quantitative Review #96, help

by nadesai » Mon Aug 16, 2010 6:57 pm
Hi,
I am unable to understand this problem from the OG Quantitative Review 2nd Ed: PLease Help with detailed solution

#96. For all z, [z] denotes the least integer greater than or equal to z. Is [x]=0?

(1) -1<x<-0.1
(2) [x+0.5] =1

OA given is A

Thanks in advance
ND
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by kvcpk » Tue Aug 17, 2010 1:13 am
nadesai wrote:Hi,
I am unable to understand this problem from the OG Quantitative Review 2nd Ed: PLease Help with detailed solution

#96. For all z, [z] denotes the least integer greater than or equal to z. Is [x]=0?

(1) -1<x<-0.1
(2) [x+0.5] =1

OA given is A

Thanks in advance
ND
Hi,

Let me try to explain this for you.
[z] represents a "step" function in mathematical terms. Knowledge of this function is not needed here. But, want to let you know what the question is asking for.
[z] gives the least integer greater than or equal to z.
[1]=1
[1.1]=2
[2.3]=4
[-1.2]=-1
[-0.5]=0

Now,
(1) -1<x<-0.1
For any value between -0.1 and -1 [not inclusive], the next greater integer is 0
Hence [x]=0
SUFF

(2) [x+0.5] =1
Let x= 0
[0.5]=1
and [x]=0.. TRUE
Let x= 0.5
[0.5+0.5] = [1]=1
[x] = 1..FALSE
INConsistent. Hence INSUFF

pick A

Hope this helps!!
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