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 Your Progress
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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
It appears that you are browsing the GMAT Club forum unregistered!
Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club
Registration gives you:
Tests
Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.
Applicant Stats
View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more
Books/Downloads
Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!
Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
Is the positive two-digit integer N less than 40 ?
(1) The units digit of N is 6 more than the tens digit --> the greatest possible value of the units digit is 9, thus the greatest possible value of the tens digit is 9-6=3, which means that N is less than 40. Sufficient.
(2) N is 4 less than 4 times the units digit. The same here: the greatest possible value of the units digit is 9, thus the greatest possible value of N is 4*9-4=32. Sufficient.
Re: Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
03 Dec 2012, 08:14
1
This post received KUDOS
1
This post was BOOKMARKED
I solved it using method of substitution.
Given number(N) is 2 digit number. So, 0<N<100. So, Question is whether N<40
Case 1: If Number N is AB, AB => A (A+6). AB => 17,28,39. hence, For sure, Number is less than 40. Option is sufficient to answer the question.
As Option A is sufficient to answer the question, Answer Choices C, E are eliminated.
Case 2: N is 4 less than 4 times the units digit. Let's N is AB N=> 4*B-4 => 4*(B-1) So, B should be greater than 5. If B =5, N =4 (Invalid case) If B =6, N =8 (Invalid case) IF B =7, N =24 If B =8, N =28 If B =9, N =32. So, For sure Number is less than 40. Option is sufficient to answer the question.
So, Either statement is sufficient to answer this question.
Re: Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
30 Dec 2012, 03:39
4
This post received KUDOS
When considering statement 2, isn't 28 the only correct number?
When units digit is 8, \((4*units)-4 = (4*8)-4 = 32 - 4 = 28\)
The units digit of N=28 is also 8. So technically, N=24 or N=32 do not even satisfy the condition. But for DS, I guess (4*9)-4 is the fastest and best way.
_________________
When considering statement 2, isn't 28 the only correct number?
When units digit is 8, \((4*units)-4 = (4*8)-4 = 32 - 4 = 28\)
The units digit of N=28 is also 8. So technically, N=24 or N=32 do not even satisfy the condition. But for DS, I guess (4*9)-4 is the fastest and best way.
You are right: 28 is the only two-digit number which satisfies the second statement.
_________________
Re: Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
12 Jan 2014, 09:30
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.
_________________
Re: Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
27 Jun 2014, 00:13
2
This post received KUDOS
Let no. be TU. (T- Ten's digit, U - Unit's digit). Also, since these are digits of a number & using the given constraint, 0<=U<=9, 1<=T<=9.
Required: 1<=T<=3 Constraints: 0<=U<=9, 1<=T<=9
A: U = T + 6 => T = U-6. Using constraints, U = 9,8,7; 1<=T<=9. This also results in 1<=T<=3. Hence, sufficient. B: 10T + U = 4U - 4 => T = (3U - 4)/10. Using constraints, U = 8; 1<=T<=9. This also results in 1<=T<=3. Hence, sufficient.
Re: Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
23 Oct 2014, 03:49
umeshpatil wrote:
I solved it using method of substitution.
Given number(N) is 2 digit number. So, 0<N<100. So, Question is whether N<40
Case 1: If Number N is AB, AB => A (A+6). AB => 17,28,39. hence, For sure, Number is less than 40. Option is sufficient to answer the question.
As Option A is sufficient to answer the question, Answer Choices C, E are eliminated.
Case 2: N is 4 less than 4 times the units digit. Let's N is AB N=> 4*B-4 => 4*(B-1) So, B should be greater than 5. If B =5, N =4 (Invalid case) If B =6, N =8 (Invalid case) IF B =7, N =24 If B =8, N =28 If B =9, N =32. So, For sure Number is less than 40. Option is sufficient to answer the question.
So, Either statement is sufficient to answer this question.
B=5 --> N=4*(B-1) = 4*(5-1)= 16 valid case similarly B=6 --> N=4*(B-1) = 4*(6-1)= 20 valid case
just wanted to correct you.
this in no way changes the answer but might confuse someone. So just trying to help.
Re: Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
10 Nov 2015, 04:14
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.
_________________
Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.
Is the positive two-digit integer N less than 40 ?
(1) The units digit of N is 6 more than the tens digit. (2) N is 4 less than 4 times the units digit.
There are 3 variables (n,a,b) and 1 equation (n=10a+b) in the original condition, 2 equations in the given conditions, making it likely that (C) will be our answer. Looking at the conditions, For 1, n=17,28,39<40 answers the question yes, and is therefore sufficient. For 2, 10a+b=4b-4, 10a+4=3b, and this answers the question 'yes' for n=28<40. This is sufficient as well, making the answer seem like (D). However, this is a logic question with commonly made mistake type 4(B).
Hence, (C) also becomes the answer but if we apply integer commonly made mistake type 4, the answer still becomes (D).
For cases where we need 2 more equation, such as original conditions with “2 variables”, or “3 variables and 1 equation”, or “4 variables and 2 equations”, we have 1 equation each in both 1) and 2). Therefore, there is 70% chance that C is the answer, while E has 25% chance. These two are the majority. In case of common mistake type 3,4, the answer may be from A, B or D but there is only 5% chance. Since C is most likely to be the answer using 1) and 2) separately according to DS definition (It saves us time). Obviously there may be cases where the answer is A, B, D or E.
_________________
Re: Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
17 Nov 2016, 09:55
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.
_________________
Re: Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
13 Jul 2017, 19:09
umeshpatil wrote:
I solved it using method of substitution.
Given number(N) is 2 digit number. So, 0<N<100. So, Question is whether N<40
Case 1: If Number N is AB, AB => A (A+6). AB => 17,28,39. hence, For sure, Number is less than 40. Option is sufficient to answer the question.
As Option A is sufficient to answer the question, Answer Choices C, E are eliminated.
Case 2: N is 4 less than 4 times the units digit. Let's N is AB N=> 4*B-4 => 4*(B-1) So, B should be greater than 5. If B =5, N =4 (Invalid case) If B =6, N =8 (Invalid case) IF B =7, N =24 If B =8, N =28 If B =9, N =32. So, For sure Number is less than 40. Option is sufficient to answer the question.
So, Either statement is sufficient to answer this question.
Can you please explain why B has to be greater than 5?
Is the positive two-digit integer N less than 40 ? [#permalink]
Show Tags
23 Jul 2017, 08:46
1
This post received KUDOS
Just list the digits and check
Statement one-The units digit of N is 6 more than the tens digit For a 2 digit no the choice available for 10's place is 1 to 9 and for units it is 0 to 9
List down all combinations starting from 1 where the units digit is 6 more than 10's
17 28 39 Sufficient- lets check one more combination-4+(4+6)=4+10=14-does not meet question condition.
Statement Two- N is 4 less than 4 times the units digit
Again list down units digits starting with 9
9*4-4= 32- Not valid as in 32 the units digit is 2 and as per the statement-4*2-4=4 8*4-4=28-Valid 7*4-4=24-not valid and so on
Hence sufficient since only one no ie 28 meets the statement 2 condition and is less than 40.
Is the positive two-digit integer N less than 40 ?
(1) The units digit of N is 6 more than the tens digit. (2) N is 4 less than 4 times the units digit.
Target question: Is N less than 40
Given: N is a positive two-digit integer
Statement 1: The units digit of N is 6 more than the tens digit This statement is, essentially, restricting the value of the tens digit. If the units digit is 6 more than the tens digit, then the tens digit cannot be very big. For example, the tens digit cannot be 8, because the units digit would have to be 14, which is impossible. Likewise, the tens digit cannot be 4, because the units digit would have to be 10, which is also impossible. So, the greatest possible value of the tens digit of N is 3. As such, N must be less than 40 Since we can answer the target question with certainty, statement 1 is SUFFICIENT
Statement 2: N is 4 less than 4 times the units digit. Well, 9 is the greatest possible value of any integer, and if the units digit were 9, then N would equal (4)(9) - 4, which is less than 40 So, no matter what value the units digit has, the resulting number (N), must be less than 40 Since we can answer the target question with certainty, statement 2 is SUFFICIENT
Version 8.1 of the WordPress for Android app is now available, with some great enhancements to publishing: background media uploading. Adding images to a post or page? Now...
Post today is short and sweet for my MBA batchmates! We survived Foundations term, and tomorrow's the start of our Term 1! I'm sharing my pre-MBA notes...
“Keep your head down, and work hard. Don’t attract any attention. You should be grateful to be here.” Why do we keep quiet? Being an immigrant is a constant...
59% (01:37) correct
