Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
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.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
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 Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemandStart 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

x=8y (how many positive odd factors does y have?)

Expert replies
by younas » Mon Apr 05, 2010 1:45 pm
Can some one explain me this problem, i have the solution but i am having hard time understanding it.

if x=8y, where y is a prime number greater than 2,how many positive odd factors does y have?

Solution:
If y is a prime number greater than 2, it must be odd. Since 8=2x2x2, the only odd factor of x will be 1 and y itself.
Picking numbers works great here, getting us around the highly abstract "math solution." Say y=3. Then x=24. The only odd factors of 24 are 1 and 3.
Join the discussion
Source: — Problem Solving |

by 4GMAT_Mumbai » Mon Apr 05, 2010 7:01 pm
Based on the answer, I guess the question should have been 'how many positive odd factors does X have?'

Try visualising the number X as a box in which its prime factors are jostling around. The box will have three 2's, one y. 'y' will be the only odd number.

1 is anyway a factor of all integers.

Hence, 1 and y are the only two +ve odd factors of X.

Hope this helps. Thanks.
Join the discussion

by eaakbari » Mon Apr 05, 2010 9:37 pm
y is a prime number. How many factors does a prime number have?
Note that any prime number will have only 2 factors and no more, that is the number itself and 1.

For instance 7= 7*1

Also as a side note you should know that 2 is the only even prime

Back to the question
It asks you for odd factors of x. Always break these kind of questions into primes(prime factorization)

x = 8y
x = 2*2*2 *y*1

We know that 2 is even and y is odd and prime ans 1 is odd too. So it has precisely 2 odd factors, y and 1.
Join the discussion

by younas » Tue Apr 06, 2010 10:55 am
Thank you very much guys this makes alot more sense now.

Once again thank you
Join the discussion