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

integer, factor, odd number, power...

Expert replies
by ska7945 » Wed Aug 20, 2008 7:57 pm
k is integer, 5^k is factor of product of odd number between 99 and 199 (inclusive), what can be the max value for k?


sorry, i dont have answer choice but oa is 13.
let's beat GMAT.
Join the discussion
Source: — Problem Solving |

by parallel_chase » Wed Aug 20, 2008 8:36 pm
list all the odd number which are multiples of 5
105 = 5
115 = 5
125 = 5*5*5
135 = 5
145 = 5
155 = 5
165 = 5
175 = 5*5
185 = 5
195 = 5

k = 13

I was able to this in less than 2 mins but any shorter way would be helpful.
Join the discussion

by vishubn » Wed Aug 20, 2008 10:35 pm
Hi

I didnt understand the stem of the question :( , could u please expalin wat is that we trtying to find coz it says product of odd number so i felt 105*110*so on ...

thanks in adavcne
Vishu
Join the discussion

by parallel_chase » Wed Aug 20, 2008 10:59 pm
The question stem says:

product of odd numbers from 99 to 199 i.e.

99*101*103*105*107*.......*199 has how many factors of 5

Hope its clear now.
Join the discussion

by sudhir3127 » Thu Aug 21, 2008 2:45 am
parallel_chase wrote:list all the odd number which are multiples of 5
105 = 5
115 = 5
125 = 5*5*5
135 = 5
145 = 5
155 = 5
165 = 5
175 = 5*5
185 = 5
195 = 5

k = 13

I was able to this in less than 2 mins but any shorter way would be helpful.
I have different method..

here it goes..

99- 199. number of odd numbers are 51

thus number of 5's are

51/5 + 51/5^2 = 12 but 125 will have 5^3 so need t take one more 5

thus its 12 + 1 =13.

hope it helps..
Join the discussion