BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

★★★★★5.0559 reviews
GMATLiveTeach 7 seats left
Chris Peckover
NEXT LIVE COHORT

Oct 13 to Jan 7, 2027

with Chris Peckover

Schedule
Tue, Thu · 8:00 to 10:00 PM ET
Included
40 live hours + 6 months of GMAT OnDemand
  • Live instruction and real-time questions
  • Class recordings and assigned practice
View class & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll
Limited cohort · enrollment openTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

Integer

Expert replies
by vinay1983 » Tue Sep 24, 2013 4:06 am
How many more positive integral factors does 2n have than the positive integer n?

1. n is an odd number

2. n is an odd prime number
You can, for example never foretell what any one man will do, but you can say with precision what an average number will be up to!
Join the discussion
Source: — Data Sufficiency |

by Brent@GMATPrepNow » Tue Sep 24, 2013 5:12 am
vinay1983 wrote:How many more positive factors does 2n have than the positive integer n?

1. n is an odd number

2. n is an odd prime number
Note: I removed the word "integral" from the question, since "factor" and "divisor" both imply integral values.

Target question: How many more positive factors does 2n have than the positive integer n?

Statement 1: n is an odd number
There are several values of n that satisfy this condition. Here are two:
Case a: n = 5, in which case n has 2 positive factors (1,5) and 2n has 4 positive factors (1,2,5,10). So, 2n has 2 more factors than n has
Case b: n = 9, in which case n has 3 positive factors (1,3,9) and 2n has 6 positive factors (1,2,3,6,9,18). So, 2n has 3 more factors than n has
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: n is an odd prime number
Since n is prime, we know that n will have only 2 positive factors (1 and n).
What about 2n?
The factors of 2n will be 1, 2, n and 2n for a total of 4 positive factors
So, 2n must have 2 more factors than n has
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer = B

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Join the discussion

by GMATGuruNY » Tue Sep 24, 2013 5:22 am
vinay1983 wrote:How many more positive integral factors does 2n have than the positive integer n?

1. n is an odd number

2. n is an odd prime number
Statement 1:
If n=1 (which has only 1 factor), then 2n = 2 (which has factors 1 and 2, for a total of 2 factors).
In this case, the difference between the number of factors = 2-1 = 1.
If n=3 (which has factors 1 and 3, for a total of 2 factors), then 2n=6 (which has factors 1, 2, 3, and 6, for a total of 4 factors).
In this case, the difference between the number of factors = 4-2 = 2.
INSUFFICIENT.

Statement 2:
If n=3 (which has factors 1 and 3, for a total of 2 factors), then 2n=6 (which has factors 1, 2, 3, and 6, for a total of 4 factors).
In this case, the difference between the number of factors = 4-2 = 2.
If n=5 (which has factors 1 and 5, for a total of 2 factors), then 2n=10 (which has factors 1, 2, 5, and 10, for a total of 4 factors).
In this case, the difference between the number of factors = 4-2 = 2.
The cases above illustrate that the difference in every case will be 2.
SUFFICIENT.

The correct answer is B.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Join the discussion