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If n is a positive integer, what is the tens digit of n ?

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If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 26 Dec 2012, 05:51
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If n is a positive integer, what is the tens digit of n ?

(1) The hundreds digit of 10n is 6.
(2) The tens digit of n + 1 is 7.
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Re: If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 26 Dec 2012, 05:53
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If n is a positive integer, what is the tens digit of n ?

(1) The hundreds digit of 10n is 6. This implies that the tens digit of n is 6. Sufficient.

(2) The tens digit of n + 1 is 7. If n=70, then the tens digit of n is 7, but if n=69, then the tens digit of n is 6. Not sufficient.

Answer: A.
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Re: If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 14 Jan 2013, 00:45
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fozzzy wrote:
How do you solve this one?


(1) The hundreds digit of 10n is 6
SUFFICIENT: If Hundred's place of 10n = 6 then Ten's place of n must be 6
e.g. n=68 tens place 6,
10n=680, hundreds place is 6

(2) The tens digit of n+1 is 7
INSUFFICIENT: If n=69; n+1=70 OR If n=77; n+1=77; i.e. n can have both 6 or 7 as tens place.

Hence choice(A) is the answer.
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Re: If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 18 May 2014, 11:11
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let n = ABCD

tens digit = C

1. 10n = ABCD0
given, hundreds digit = 6 (or) C = 6 - sufficient

2. tens digit of n+1 = 7.

consider CD = 69 -> CD+1 = 70 -> C=6 (or)

consider CD = 71 ->CD+1 = 72 -> C = 7

2 cases possible - insuff.

Hence A
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If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 24 Jun 2015, 05:59
If n = 60, then the tens digit is 6
10*n = 600, then the tens digit is 0.

if n = 66, then the tens digit is 6
10*n = 660, then the tens digit is also 6.


Therefore 1. seems (incorrectly) not sufficient to me.

What am I doing wrong?


Damn it, it says "hundreds" digit in 1., not tens digit... :S
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Re: If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 21 Jul 2016, 16:32
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Walkabout wrote:
If n is a positive integer, what is the tens digit of n ?

(1) The hundreds digit of 10n is 6.
(2) The tens digit of n + 1 is 7.


Target question: What is the tens digit of n?

Statement 1: The hundreds digit of 10n is 6
Notice what happens when we multiply any positive integer by 10:
34 x 10 = 340
60 x 10 = 600
128 x 10 = 1280
54629 x 10 = 546290
The tens digit in the original number becomes the hundreds digit in the new number.

So, if we're told that the hundreds digit of 10n is 6, then we know that the tens digit in n must be 6
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: The tens digit of n+1 is 7
There are several values of n that meet this condition. Here are two:
case a: n=69 in which case the tens digit of n is 6
case b: n=74 in which case the tens digit of n is 7
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT


Answer =

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If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 09 Sep 2016, 09:59
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Here is my contribution with the reasoning a little more visual for those still struggling. :wink:
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Re: If N is a positive integer, what is the tens digit of N  [#permalink]

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New post 13 Oct 2016, 00:10
Akuthiala wrote:
If N is a positive integer, what is the tens digit of N

(1) The hundreds digit of 10N is 6
(2) the tens digit of N+1 is 7


Answer will be A.

Statement 1 : Hundreds digit of 10N = Tens digit of N = 6. Hence, sufficient.

Statement 2: Tends digit of N+1 = 7.

Now in this case it may happen that Units digit was 9 and when 1 was added, we got Tends digit as 7. In that case answer will be 6. BUT if Units is less than 9, answer would be 7. Hence, Insufficient.
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Re: If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 13 Oct 2016, 01:10
Walkabout wrote:
If n is a positive integer, what is the tens digit of n ?

(1) The hundreds digit of 10n is 6.
(2) The tens digit of n + 1 is 7.


let the number be in the form

100a+10b+c = n what is 10b

from
1000a+100b+10c + d = 10n , now the 100s digit (b=6) in 10n is the tens in n .......suff

from 2

n+1 = 100a+ 10b+(c+1) ... if c+1>=10 then b = 6 but if c+1<10 b = 7... insuff

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If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 21 Mar 2018, 08:00
Walkabout wrote:
If n is a positive integer, what is the tens digit of n?

(1) The hundreds digit of 10n is 6.
(2) The tens digit of n + 1 is 7.


I am thinking that if we had the question as

If n is a positive number, what is the tenth digit of n?
(1) The hundredth digit of 10n is 6.
(2) The tenth digit of n + 1 is 7

A is no longer sufficient Am I Mistaken?


My answer would be B

What do you think guys!
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Re: If n is a positive integer, what is the tens digit of n ?  [#permalink]

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New post 21 Mar 2018, 22:56
mohd_int wrote:
Walkabout wrote:
If n is a positive integer, what is the tens digit of n?

(1) The hundreds digit of 10n is 6.
(2) The tens digit of n + 1 is 7.


I am thinking that if we had the question as

If n is a positive number, what is the tenth digit of n?
(1) The hundredth digit of 10n is 6.
(2) The tenth digit of n + 1 is 7

A is no longer sufficient Am I Mistaken?


My answer would be B

What do you think guys!


Hello

Yes if you change the question to find the 'tenth' digit rather than 'tens' digit with the same set of statements as in this question, then the answer should be B, I think.

I suggest you post this question of yours to the DS forum.
Re: If n is a positive integer, what is the tens digit of n ? &nbs [#permalink] 21 Mar 2018, 22:56
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