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 Starts Oct 17
Chris Peckover, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Chris Peckover, 100th-Percentile GMAT Scorer

Oct 17 · Chris Peckover
Sat · 11:00 AM to 2:00 PM ET
Oct 20 · Chris Peckover
Tue, Thu · 8:00 to 10:00 PM ET
Oct 25 · Josh Braslow
Sun · 1:00 to 4:00 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
EALiveTeachOnDemand 5 seats left Start anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

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

Jars ratio

Expert replies
by GmatKiss » Mon Aug 15, 2011 5:06 am
A jar contains 8 red marbles and y white marbles. If Joan takes 2 random marbles from the jar, is it more likely that she will have 2 red marbles than that she will have one marble of each color?

(1) y ≤ 8
(2) y ≥ 4
Join the discussion
Source: — Data Sufficiency |

by sumgb » Mon Aug 15, 2011 11:39 am
let's put the probability of selecting both red marbles:
{8 / (8+y)}{7/(7+y)}

probability of 1 of each color:
{8 / (8+y)}{y/(7+y)}

what you need to find out in this question is:
{8 / (8+y)}{7/(7+y)} > {8 / (8+y)}{y/(7+y)} which means

56 / {(8+y)(7+y)} > 8y / {(8+y)(7+y)} which means
56 > 8y which means
7 > y that is Is y < 7?

stmnt 1: y ≤ 8 clearly insuff; cross off A D
stmnt 2: y ≥ 4 also insuff; cross off B

together we have 4 <= y <= 8; also insuff as y could still be 8; cross off C

Answer E

What is OA and OE?

Hope this helps...
Join the discussion

by beatthegmat.garry » Mon Aug 15, 2011 9:54 pm
Let total number of possible ways of selecting any 2 marbles be 'S'.

probability of selecting 2 red marbles=8C2/S=28/S. ......(i)

probability of selecting 1 red and 1 white marble=8C1*YC1/S. ...... (ii)

Now if Y>=4 then YC1=4C1=4 which will render (ii) greater than (i).

Statement (1): Y<=8 . No sufficient as Y can be 2 or 8

Statement (2): Y>=4 . Sufficient as Y is >=4
Last edited by beatthegmat.garry on Mon Aug 15, 2011 10:09 pm, edited 1 time in total.
Join the discussion

by Frankenstein » Mon Aug 15, 2011 10:04 pm
beatthegmat.garry wrote:Let total number of possible ways of selecting any 2 marbles be 'S'.

probability of selecting 2 red marbles=8C2/S=28/S. ......(i)

probability of selecting 1 red and 1 white marble=8C1*YC1/S. ...... (ii)

Now if Y>=3 then YC1=3C1=3 which will render (ii) greater than (i).


Statement (1): Y<=8 . No sufficient as Y can be 2 or 8

Statement (2): Y>=4 . Sufficient as Y is >=3
Hi,
Almost correct but minor error. For y=3, (ii) is not greater than (i)
For y>=4, (ii) > (i)
Is 28/S > 8y/S? => Is y<7/2
So, if y<=3, the answer is yes
if y>=4, answer is No.
statement(2) is sufficient

Hence, B
Cheers!

Things are not what they appear to be... nor are they otherwise
Join the discussion

by beatthegmat.garry » Mon Aug 15, 2011 10:10 pm
Thanks Frankenstein :)
Join the discussion

by sumgb » Mon Aug 15, 2011 11:40 pm
Yes indeed.
let's put the probability of selecting both red marbles:
{8 / (8+y)}{7/(7+y)}

probability of 1 of each color:
{8 / (8+y)}{y/(7+y)}

what you need to find out in this question is:
{8 / (8+y)}{7/(7+y)} > {8 / (8+y)}{y/(7+y)} which means

56 / {(8+y)(7+y)} > 8y / {(8+y)(7+y)} which means
56 > 8y which means
7 > y that is Is y < 7?
This is wrong.
probability of 1 of each color:
{8 / (8+y)}{y/(7+y)}
this should be -
2{8 / (8+y)}{y/(7+y)}

so is y < 3.5

clearly stmnt 2 is the winner. :-)

Thanks guys...
Join the discussion

by GmatKiss » Tue Aug 16, 2011 12:40 am
OA: B
Join the discussion