One more conflicting explanation if n is a positive integer,

Question

One more conflicting explanation 

if n is a positive integer, 

is (1/10)^^n 2 
(2) (1/10)^^n-1 < 0.1 

guys & girls post your explanations please 

thanks

bewakoof · Answer

D

1/10 ^ n < 0.01 then n > 2


for s2. 1/10^ n-1 < 0.1.. 

we know 1/10 = 0.1.. n-1 < 1.. n <2.. if n < 2.. than. . (1/10)^^n < 0.01 does not hold true .. 

i hope this makes sense

gmatkrishna · Answer

D

1/10 ^ n < 0.01 then n > 2

for s2. 1/10^ n-1 < 0.1..

we know 1/10 = 0.1.. n-1 < 1.. n <2.. if n < 2.. than. . (1/10)^^n < 0.01 does not hold true ..

i hope this makes sense

-------

statement (2) holds only for n > 2 isn't?
But that's not mentioned in the question stem at all

and (2) doesn't hold for n < 2

which is INSUFFICIENT to conclude, isn't?

My understanding (please correct me if I am wrong) is that in any yes or no type
data sufficiency questions, one cannot have conflicting answers/conclusion from a statement which looks like the case of statement (2) from the above example

Please explain

bewakoof · Answer

that can be derived from st2. 

so we know n <2.. lets take n = 1.. in that case.. 1/10 ^ n = 0.1.. 
n = 0, 1/10 ^ n = 1.. the question is asking is (1/10)^n < 0.01.. no .. 1/10 ^n is not less that 0.01..

MBAHopeful · Answer

I would go with D.
1) Is clearly sufficient
2) From the given stem we can that to satisfy the condition n must be >= 3 and for n > 2 we can see that (1/10)^^n < 0.01 is true.

I hope this makes sense.

Nayan · Answer

Can somebody pls explain this??

"we know 1/10 = 0.1.. n-1 < 1.. n <2.. if n < 2.. than. . (1/10)^^n < 0.01 does not hold true "

I didn't understand how n-1<1

anandsebastin · Answer

Let me see if I can make this a bit clearer. 
For statement 2 to be true, 
(1/10)^(n-1)<0.1
Let's take n=1, then (1/10)n-1 = 1
If n=2, then (1/10)2-1=0.1
If n=3, then (1/10)(3-1)=0.01 Satisfies the condition, therefore, n should at least be 3 or more. 

In that case (1/10)^n <.01 is true.
Hence D.

One more conflicting explanation if n is a positive integer,

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