Author 
Message 
TAGS:

Hide Tags

Manager
Joined: 26 Mar 2007
Posts: 72
Concentration: General Management, Leadership

Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
22 Nov 2011, 03:04
Question Stats:
43% (02:07) correct 57% (01:41) wrong based on 324 sessions
HideShow timer Statistics
Given that R is positive threedigit integer, what is the hundreds digit of R? 1. The hundreds digit of 3R is 8 2. (R+1) results in a number with the hundreds digit of 9. Source : 800score.com
Official Answer and Stats are available only to registered users. Register/ Login.



Intern
Joined: 20 Aug 2010
Posts: 34

Re: Hundreds digit of R? [#permalink]
Show Tags
22 Nov 2011, 05:17
1. R could be e.g 280 * 3 = 840 or 940 * 3 = 2820  insuff 2. R could be 899 or 900  insuff 1+2. R should be > 934  suff C



Senior Manager
Joined: 28 Jul 2011
Posts: 412
Location: United States
Concentration: International Business, General Management
GPA: 3.86
WE: Accounting (Commercial Banking)

Re: Hundreds digit of R? [#permalink]
Show Tags
22 Nov 2011, 06:51
Initially made silly mistake +1 C
_________________
+1 Kudos If found helpful..



Manager
Joined: 16 Dec 2009
Posts: 69
WE: Information Technology (Commercial Banking)

Re: Hundreds digit of R? [#permalink]
Show Tags
25 Nov 2011, 05:53
Made the same silly mistake on both the options.. . Picked (D)
_________________
If Electricity comes from Electrons , Does Morality come from Morons ??
If you find my post useful ... then please give me kudos ......
h(n) defined as product of even integers from 2 to n Number N divided by D leaves remainder R Ultimate list of MBA scholarships for international applicants



Director
Status: My Thread Master Bschool Threads>Krannert(Purdue),WP Carey(Arizona),Foster(Uwashngton)
Joined: 28 Jun 2011
Posts: 842

Re: Hundreds digit of R? [#permalink]
Show Tags
25 Nov 2011, 12:03
I too picked D thinking r=870/3......
C +1



Manager
Joined: 12 Oct 2011
Posts: 225

Re: Hundreds digit of R? [#permalink]
Show Tags
04 Jan 2012, 12:24
Oh nice question. Very tricky. C is the answer. The first statement could lead to multiple values for the hundreds digit. The second statement could also lead to two values for the hundreds digit. However, together, the two statements can lead only to one value  9  for the hundreds digit of the 3digit number.
_________________
Consider KUDOS if you feel the effort's worth it



Manager
Joined: 29 Jul 2011
Posts: 98
Location: United States

Re: Hundreds digit of R? [#permalink]
Show Tags
04 Jan 2012, 14:03
Oops! Got S1 analysis incorrect, S2 correct. I picked A. For S1, I totally ignored that the number could be 4 digit. It is these simple, yet tricky, twists that I fear of.
_________________
I am the master of my fate. I am the captain of my soul. Please consider giving +1 Kudos if deserved!
DS  If negative answer only, still sufficient. No need to find exact solution. PS  Always look at the answers first CR  Read the question stem first, hunt for conclusion SC  Meaning first, Grammar second RC  Mentally connect paragraphs as you proceed. Short = 2min, Long = 34 min



SVP
Joined: 06 Sep 2013
Posts: 1882
Concentration: Finance

Re: Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
27 Mar 2014, 06:16
Again let’s think about this for a second. First we have that ABC * 3 has a hundreds digit of 8. This ain't gonna tell us much so insuff. Now,
Second statement says that abc + 1 has hundreds digit of 9. Now the max value for tens and units digit respectively are 9 and 9. Then we only have 1 carried over to the units digit. Therefore a is either 8 or 9.
Now, let's try with both statements together. If we have 8XX * 3 = 4 as hundreds digit and we would need a carry over of 4 to reach 8 in the hundreds digit as per statement 1. This is not possible because even if b = 9 the maximum carry over we can get is 2 (29 if both units digit and tens digit are equal to 9). Therefore this option is not possible. What if hundreds digit is 9? Then we wil have that 3*9=27 so 7 for hundreds digit we would need only a carry over of 1 which is indeed possible. Hence only 9 works. C
Hope this helps Cheers J



Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 8102
Location: Pune, India

Re: Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
02 Oct 2015, 00:46
kannn wrote: Given that R is positive threedigit integer, what is the hundreds digit of R?
1. The hundreds digit of 3R is 8 2. (R+1) results in a number with the hundreds digit of 9.
Source : 800score.com Responding to a pm: 1. The hundreds digit of 3R is 8 When you multiply a number by 3, the hundreds digit will be obtained by multiplying the hundreds digit of the original number by 3 and adding any carryover we might have. 3 * 9 (the largest digit) is 27 so the maximum carryover we can get from tens digit multiplication is 2 (even if the units digit of the original number is also 9, we will get 2 as carryover from units to tens and still 2 as carryover from tens to hundreds). No carry over: 6 times 3 is 18. 611 > 611 * 3 = 1833 One carry over: We need to obtain 7 in the hundreds place. 9 times 3 is 27. 961 > 961 * 3 = 2883 Two carry over: We need to obtain 6 in hundreds place. 2 times 3 is 6. 291 > 291 * 3 = 873 The hundreds digit can be 2, 6 or 9. 2. (R+1) results in a number with the hundreds digit of 9. R can be an number from 899 to 998. The hundreds digit can be 8 or 9. Using both statements, we see that the only common hundreds digit we have is 9. Hence the hundreds digit must be 9. Answer (C)
_________________
Karishma Veritas Prep  GMAT Instructor My Blog
Get started with Veritas Prep GMAT On Demand for $199
Veritas Prep Reviews



Intern
Status: Learning
Joined: 07 Aug 2011
Posts: 37
Location: India
Schools: WBUT  Class of 2011
GMAT Date: 01062014
GPA: 2.6
WE: Research (Education)

Re: Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
03 Oct 2015, 03:58
But the question is saying that R is positive threedigit integer
_________________
If you like my post give me kudos.
Arindam Sur Researcher, Academian



Manager
Joined: 01 Jan 2015
Posts: 63

Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
Updated on: 04 Oct 2015, 10:51
kannn wrote: Given that R is positive threedigit integer, what is the hundreds digit of R?
1. The hundreds digit of 3R is 8 2. (R+1) results in a number with the hundreds digit of 9.
Source : 800score.com I believe the correct answer to this question should be changed to answer choice A.The question stem says R is a 3 digit number.Let'say R is represented by digits A,B,and C, where A is a digit between 1 and 9 inclusive and B and C are digits between 0 and 9 inclusive. (1) R= ABC can be written as R=100*A+10*B+C. 3*R can be written as 300*A+30*B+3*C. The maximum value of 30*B+3*C is 297 when B and C are each 9. Since it is required that 300*A+30*B+3*C > 800, if we minimize A we get, 300*A > 503. But A cannot be greater than or equal to 3, because then the number would be at least 900 and the hundreds digit of 3R will no longer be 8. So A must be 2. First statement is sufficient (2) You can easily find this statement insufficient by taking numbers 899 and 900. The hundreds digit of R can be 8 or 9, hence insufficient. Correct answer choice is A.
Originally posted by bhaskar438 on 03 Oct 2015, 14:10.
Last edited by bhaskar438 on 04 Oct 2015, 10:51, edited 1 time in total.



Manager
Joined: 01 Jan 2015
Posts: 63

Re: Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
03 Oct 2015, 14:15
VeritasPrepKarishma wrote: kannn wrote: Given that R is positive threedigit integer, what is the hundreds digit of R?
1. The hundreds digit of 3R is 8 2. (R+1) results in a number with the hundreds digit of 9.
Source : 800score.com Responding to a pm: 1. The hundreds digit of 3R is 8 When you multiply a number by 3, the hundreds digit will be obtained by multiplying the hundreds digit of the original number by 3 and adding any carryover we might have. 3 * 9 (the largest digit) is 27 so the maximum carryover we can get from tens digit multiplication is 2 (even if the units digit of the original number is also 9, we will get 2 as carryover from units to tens and still 2 as carryover from tens to hundreds). No carry over: 6 times 3 is 18. 611 > 611 * 3 = 1833 One carry over: We need to obtain 7 in the hundreds place. 9 times 3 is 27. 961 > 961 * 3 = 2883 Two carry over: We need to obtain 6 in hundreds place. 2 times 3 is 6. 291 > 291 * 3 = 873 The hundreds digit can be 2, 6 or 9. 2. (R+1) results in a number with the hundreds digit of 9. R can be an number from 899 to 998. The hundreds digit can be 8 or 9. Using both statements, we see that the only common hundreds digit we have is 9. Hence the hundreds digit must be 9. Answer (C) Hi VeritasPrepKarishma, It is given that R is a 3 digit positive integer. Shouldn't the correct answer be choice A?



Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 8102
Location: Pune, India

Re: Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
04 Oct 2015, 00:41
bhaskar438 wrote: VeritasPrepKarishma wrote: kannn wrote: Given that R is positive threedigit integer, what is the hundreds digit of R?
1. The hundreds digit of 3R is 8 2. (R+1) results in a number with the hundreds digit of 9.
Source : 800score.com Responding to a pm: 1. The hundreds digit of 3R is 8 When you multiply a number by 3, the hundreds digit will be obtained by multiplying the hundreds digit of the original number by 3 and adding any carryover we might have. 3 * 9 (the largest digit) is 27 so the maximum carryover we can get from tens digit multiplication is 2 (even if the units digit of the original number is also 9, we will get 2 as carryover from units to tens and still 2 as carryover from tens to hundreds). No carry over: 6 times 3 is 18. 611 > 611 * 3 = 1833 One carry over: We need to obtain 7 in the hundreds place. 9 times 3 is 27. 961 > 961 * 3 = 2883 Two carry over: We need to obtain 6 in hundreds place. 2 times 3 is 6. 291 > 291 * 3 = 873 The hundreds digit can be 2, 6 or 9. 2. (R+1) results in a number with the hundreds digit of 9. R can be an number from 899 to 998. The hundreds digit can be 8 or 9. Using both statements, we see that the only common hundreds digit we have is 9. Hence the hundreds digit must be 9. Answer (C) Hi VeritasPrepKarishma, It is given that R is a 3 digit positive integer. Shouldn't the correct answer be choice A?R is a three digit number but 3R needn't be. It could have 4 digits. In each of the cases shown, R has 3 digits and the hundreds digit is different. So stmnt 1 is not enough.
_________________
Karishma Veritas Prep  GMAT Instructor My Blog
Get started with Veritas Prep GMAT On Demand for $199
Veritas Prep Reviews



Manager
Joined: 01 Jan 2015
Posts: 63

Re: Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
04 Oct 2015, 11:21
VeritasPrepKarishma wrote: R is a three digit number but 3R needn't be. It could have 4 digits. In each of the cases shown, R has 3 digits and the hundreds digit is different. So stmnt 1 is not enough. Yes you are right! Perhaps it is best to avoid an algebraic approach such as the one I did for a multiplication problem such as this. I will leave that algebraic approach for addition and subtraction questions. +1 Kudos to you.



Manager
Joined: 01 Jan 2015
Posts: 63

Re: Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
04 Oct 2015, 11:24
kannn wrote: Given that R is positive threedigit integer, what is the hundreds digit of R?
1. The hundreds digit of 3R is 8 2. (R+1) results in a number with the hundreds digit of 9.
Source : 800score.com Here is an alternate method to show statement 1 is insufficient without looking at carryover. 3R is a multiple of 3, therefore its sum of digits should be a multiple of 3. In the case 3R is a 4 digit number, the thousands digit can only be 1 or 2 (the largest 3 digit number, 999, multiplied by 3 is smaller than 3000). After applying statement 1, the hundreds digit is now 8. Let's say 3R is represented by XYZW, where X has a digit value of 1 or 2, Y has a digit value of 8, and Z and W each can be a digit between 0 and 9 inclusive. Case 1: X=1 and Y=8 1+8+Z+W = Multiple of 3Ex: If Z+W = 0. Then R = 600. The hundreds digit of R is 6. Case 2: X=2 and Y=8 2+8+Z+W = Multiple of 3Ex: If Z and W each equal 1, then 3R =2811 > R=927. The hundreds digit of R is 9. Statement 1 is insufficient.



NonHuman User
Joined: 09 Sep 2013
Posts: 7020

Re: Given that R is positive threedigit integer, what is the [#permalink]
Show Tags
10 Jun 2018, 23:05
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.
_________________
GMAT Books  GMAT Club Tests  Best Prices on GMAT Courses  GMAT Mobile App  Math Resources  Verbal Resources




Re: Given that R is positive threedigit integer, what is the
[#permalink]
10 Jun 2018, 23:05






