It is currently 17 Nov 2017, 22:13

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

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

Author Message
TAGS:

Hide Tags

Manager
Joined: 02 Dec 2012
Posts: 178

Kudos [?]: 3570 [3], given: 0

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

Show Tags

26 Dec 2012, 05:51
3
KUDOS
42
This post was
BOOKMARKED
00:00

Difficulty:

35% (medium)

Question Stats:

67% (00:58) correct 33% (01:09) wrong based on 1550 sessions

HideShow timer Statistics

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.
[Reveal] Spoiler: OA

Kudos [?]: 3570 [3], given: 0

Math Expert
Joined: 02 Sep 2009
Posts: 42248

Kudos [?]: 132526 [0], given: 12324

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

Show Tags

26 Dec 2012, 05:53
Expert's post
10
This post was
BOOKMARKED
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.

_________________

Kudos [?]: 132526 [0], given: 12324

Current Student
Joined: 27 Jun 2012
Posts: 405

Kudos [?]: 947 [3], given: 184

Concentration: Strategy, Finance
Re: If n is a positive integer, what is the tens digit of n ? [#permalink]

Show Tags

14 Jan 2013, 00:45
3
KUDOS
3
This post was
BOOKMARKED
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.

_________________

Thanks,
Prashant Ponde

Tough 700+ Level RCs: Passage1 | Passage2 | Passage3 | Passage4 | Passage5 | Passage6 | Passage7
VOTE GMAT Practice Tests: Vote Here
PowerScore CR Bible - Official Guide 13 Questions Set Mapped: Click here

Kudos [?]: 947 [3], given: 184

Manager
Joined: 18 May 2014
Posts: 62

Kudos [?]: 20 [5], given: 6

Location: United States
Concentration: General Management, Other
GMAT Date: 07-31-2014
GPA: 3.99
WE: Analyst (Consulting)
Re: If n is a positive integer, what is the tens digit of n ? [#permalink]

Show Tags

18 May 2014, 11:11
5
KUDOS
1
This post was
BOOKMARKED
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

Kudos [?]: 20 [5], given: 6

Manager
Joined: 07 Apr 2015
Posts: 180

Kudos [?]: 70 [0], given: 185

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

Show Tags

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

Kudos [?]: 70 [0], given: 185

SVP
Joined: 12 Sep 2015
Posts: 1840

Kudos [?]: 2590 [3], given: 362

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

Show Tags

21 Jul 2016, 16:32
3
KUDOS
Expert's post
Top Contributor
3
This post was
BOOKMARKED
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

[Reveal] Spoiler:
A

RELATED VIDEO

_________________

Brent Hanneson – Founder of gmatprepnow.com

Kudos [?]: 2590 [3], given: 362

Manager
Joined: 23 Jun 2009
Posts: 201

Kudos [?]: 108 [1], given: 138

Location: Brazil
GMAT 1: 470 Q30 V20
GMAT 2: 620 Q42 V33
If n is a positive integer, what is the tens digit of n ? [#permalink]

Show Tags

09 Sep 2016, 09:59
1
KUDOS
Here is my contribution with the reasoning a little more visual for those still struggling.
Attachments

Screenshot_20160909-140502.jpg [ 504.88 KiB | Viewed 9507 times ]

Kudos [?]: 108 [1], given: 138

Board of Directors
Status: Aiming MBA
Joined: 18 Jul 2015
Posts: 2748

Kudos [?]: 904 [0], given: 67

Location: India
GPA: 3.65
WE: Information Technology (Health Care)
Re: If N is a positive integer, what is the tens digit of N [#permalink]

Show Tags

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

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.
_________________

How I improved from V21 to V40! ?

Kudos [?]: 904 [0], given: 67

Retired Moderator
Joined: 05 Jul 2006
Posts: 1749

Kudos [?]: 442 [0], given: 49

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

Show Tags

13 Oct 2016, 01:10
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

A

Kudos [?]: 442 [0], given: 49

Non-Human User
Joined: 09 Sep 2013
Posts: 15710

Kudos [?]: 281 [0], given: 0

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

Show Tags

22 Oct 2017, 17:28
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

Kudos [?]: 281 [0], given: 0

Re: If n is a positive integer, what is the tens digit of n ?   [#permalink] 22 Oct 2017, 17:28
Display posts from previous: Sort by