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

Pls Explain

Expert replies
by Nycgrl » Wed Aug 06, 2008 3:27 pm
Of the science books in a certain supply room, 50 are on botany, 65 are on zoology, 90 are on physics. 50 are on geology, and 110 are on chemistry. If science books are removed randomly from the supply room, how many must be removed to ensure that 80 of the books removed are on the same science?
(A) 81
(B) 159
(C) 166
(D) 285
(E) 324
Join the discussion
Source: — Problem Solving |

by parallel_chase » Wed Aug 06, 2008 3:49 pm
You want to remove 80 books of the same science.

Lets take the worst case scenario.

remove 79 from botany = we only have 50
remove 79 from zoology= we only have 65
remove 79 from physics =79
remove 79 from geology= we only have 50
remove 79 from chemistry= 79

50+65+79+50+79= 323

Now we just have to pick 1 more book to make sure we at least have 80 of same science

323+1=324

Let me know if you have any doubts.
Join the discussion

by Nycgrl » Wed Aug 06, 2008 3:51 pm
I solved this question like this only but OA is 81.
Join the discussion

by parallel_chase » Wed Aug 06, 2008 4:00 pm
Nycgrl wrote:I solved this question like this only but OA is 81.
The OA is 324. I solved this question yesterday, refer this

https://www.beatthegmat.com/science-book ... html#65305
Join the discussion

by Wakka Wakka » Wed Aug 06, 2008 4:03 pm
dumb question what is OA?
Join the discussion

by Nycgrl » Wed Aug 06, 2008 4:10 pm
parallel_chase wrote:
Nycgrl wrote:I solved this question like this only but OA is 81.
The OA is 324. I solved this question yesterday, refer this

https://www.beatthegmat.com/science-book ... html#65305

Thanks Parallel_chase
Join the discussion

by Wakka Wakka » Wed Aug 06, 2008 4:11 pm
nevermind...tired...time to stop studying
Join the discussion