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

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

From a seven-member dance group, four will be chosen at

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Moderator
Posts: 2558
Joined: Sun Oct 15, 2017 1:50 pmFollowed by: 6 members
by BTGmoderatorLU » Wed Jul 03, 2019 2:33 pm

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty—

Source: Veritas Prep

From a seven-member dance group, four will be chosen at random to volunteer at a youth dance event. If Kori and Jason are two of the seven members, what is the probability that both will be chosen to volunteer?

A. \(1/21\)
B. \(1/7\)
C. \(4/21\)
D. \(2/7\)
E. \(3/7\)

The OA is D
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3008
Joined: Mon Aug 22, 2016 6:19 amFollowed by: 34 members
Location: Grand Central / New York
Thanked: 470 times

by Jay@ManhattanReview » Wed Jul 03, 2019 10:48 pm
BTGmoderatorLU wrote:Source: Veritas Prep

From a seven-member dance group, four will be chosen at random to volunteer at a youth dance event. If Kori and Jason are two of the seven members, what is the probability that both will be chosen to volunteer?

A. \(1/21\)
B. \(1/7\)
C. \(4/21\)
D. \(2/7\)
E. \(3/7\)

The OA is D
Number of ways such that any of the 4 dances are chosen randomly = 7C4;
Number of ways such that Kori and Jason are selected and any of the remaining 2 dances are chosen randomly = 5C2;

Required probability = 5C2 / 7C4 = 2/7

The correct answer: D

Hope this helps!

-Jay
_________________
Manhattan Review GMAT Prep

Locations: GRE Manhattan | ACT Prep Courses San Francisco | IELTS Prep Courses Boston | Seattle IELTS Tutoring | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 2548
Joined: Sun Oct 29, 2017 2:04 pmFollowed by: 6 members

by swerve » Thu Jul 04, 2019 11:43 am
Hi, you can try as follows:

There are 7 members including Kori and Jason. We are to find the probability of choosing these two if we are selecting 4 out of these 7.
Way to choose 4 out of \(7= 7C4=35\).

Now two out of 4 are Kori and Jason. The remaining 2 are to be chosen from remaining 5. (K and J are not included as they are already chosen).

So \(5C2=10\).
prob \(=10/35 \Rightarrow\) D
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 8157
Joined: Sat Apr 25, 2015 10:56 amFollowed by: 29 members
Location: Los Angeles, CA
Thanked: 43 times

by Scott@TargetTestPrep » Sat Jul 06, 2019 5:08 pm
BTGmoderatorLU wrote:Source: Veritas Prep

From a seven-member dance group, four will be chosen at random to volunteer at a youth dance event. If Kori and Jason are two of the seven members, what is the probability that both will be chosen to volunteer?

A. \(1/21\)
B. \(1/7\)
C. \(4/21\)
D. \(2/7\)
E. \(3/7\)

The OA is D
We are given that from 7 members, 4 people will be selected for a dance team. We need to determine the probability that both Kori and Jason will be selected.

Let's first determine the total number of ways to select 4 people from a group of 7 people.

The number of ways to select 4 people from a group of 7 is:

7C4 = 7! / (3! x 4!) = (7 x 6 x 5 x 4) / 4! = (7 x 6 x 5 x 4) / (4 x 3 x 2 x 1) = 7 x 5 = 35

Next, we need to determine the number of ways the group can be selected when both Kori and Jason are selected. Since they both must be selected, there are 5 remaining people for the 2 remaining spots. We can select 2 people from 5 in the following ways:

5C2 = 5! / (3! x 2!) = (5 x 4) / 2! = 20/2 = 10

Thus, the probability of creating a 4-person dance team that includes both Kori and Jason is 10/35 = 2/7.

Answer: D

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1