NEW HERE? LEARN MORE
closeclose
Last visit was: 24 Apr 2024, 19:15 It is currently 24 Apr 2024, 19:15
Decision Tracker
My Rewards
New posts
New comers' posts

Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

A pair of fair six-sided dice is rolled. If at least one of the dice

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92900
Own Kudos [?]: 618824 [14]
Given Kudos: 81588
Send PM
CAT Tests Forum Quiz Mode
A pair of fair six-sided dice is rolled. If at least one of the dice [#permalink] New post   15 Jun 2020, 07:21
2
Kudos
12
Bookmarks
Expert Reply
00:00
A
B
C
D
E

Difficulty:

95% (hard)

Question Stats:

26% (01:26) correct 74% (01:07) wrong based on 101 sessions
Hide Show timer Statistics
A pair of fair six-sided dice is rolled. If at least one of the dice is a 1. What is the probability that both dice are showing a 1?

A. 1/12
B. 1/11
C. 1/10
D. 1/6
E. 1/2


Are You Up For the Challenge: 700 Level Questions
ShowHide Answer
Official Answer
B
User avatar
S
Babineaux
Manager
Manager
Joined: 24 May 2018
Posts: 96
Own Kudos [?]: 98 [0]
Given Kudos: 35
Location: India
Concentration: General Management, Human Resources
WE:Engineering (Energy and Utilities)
Send PM
Re: A pair of fair six-sided dice is rolled. If at least one of the dice [#permalink] New post   15 Jun 2020, 08:19
Already given at least one of the dice is at 1.

Then the answer lies within other dice, when it will be at 1 the event will be satisfied.

Thus for both the dices at 1, the probability will be 1/6.

IMO ans is D.
User avatar
L
shameekv1989
Director
Director
Joined: 14 Dec 2019
Posts: 829
Own Kudos [?]: 888 [1]
Given Kudos: 354
Location: Poland
Concentration: Entrepreneurship, Strategy
Schools: Cambridge '22 (D) WBS (A$) IIMA PGPX'22 (D) WHU MBA (WD) ISB'22 (D)
GMAT 1: 640 Q49 V27
GMAT 2: 660 Q49 V31
GMAT 3: 720 Q50 V38
GPA: 4
WE:Engineering (Consumer Electronics)
Send PM
GMAT ToolKit User Reviews Badge
Re: A pair of fair six-sided dice is rolled. If at least one of the dice [#permalink] New post   15 Jun 2020, 13:41
1
Bookmarks
Bunuel wrote:
A pair of fair six-sided dice is rolled. If at least one of the dice is a 1. What is the probability that both dice are showing a 1?

A. 1/12
B. 1/11
C. 1/10
D. 1/6
E. 1/2


Are You Up For the Challenge: 700 Level Questions


1_ or _1 or 11

_ can take 5 values

Total ways = 5+5+1 = 11

Therefore probability of 1,1 on two dices will be 1/11

Answer - B
User avatar
L
AnirudhaS
LBS Moderator
Joined: 30 Oct 2019
Posts: 836
Own Kudos [?]: 775 [2]
Given Kudos: 1577
Send PM
Re: A pair of fair six-sided dice is rolled. If at least one of the dice [#permalink] New post   15 Jun 2020, 22:36
2
Kudos
The trick to the problem is realising that the event (1,1) is ONE event.
(1,1) --> Same event
(1,2)
(1,3)
(1,4)
(1,5)
(1,6)

(1,1) --> Same event
(2,1)
(3,1)
(4,1)
(5,1)
(6,1)

Total no. of possible events = 11
One occurs in both the throws = 1 way
Required probability =\( \frac{1}{11}\)

Answer: B
User avatar
G
sambitspm
Senior Manager
Senior Manager
Joined: 05 Aug 2019
Posts: 317
Own Kudos [?]: 279 [0]
Given Kudos: 130
Location: India
Concentration: Leadership, Technology
GMAT 1: 600 Q50 V22
GMAT 2: 670 Q50 V28 (Online)
GPA: 4
Send PM
Re: A pair of fair six-sided dice is rolled. If at least one of the dice [#permalink] New post   16 Jun 2020, 06:31
There are 3 cases (first dice, second dice) => (1,x) , (1,1) , (x,1). x!=1
Total Probability = 1/6 * 5/6 + 1/6+1/6 + 5/6*1/6
Favourable Probability = 1/6*1/6

Answer = 1/(5+1+5)= 1/11
IMO B
User avatar
G
Regor60
Senior Manager
Senior Manager
Joined: 21 Nov 2021
Posts: 437
Own Kudos [?]: 209 [0]
Given Kudos: 344
Send PM
Re: A pair of fair six-sided dice is rolled. If at least one of the dice [#permalink] New post   08 Oct 2022, 11:21
Bunuel wrote:
A pair of fair six-sided dice is rolled. If at least one of the dice is a 1. What is the probability that both dice are showing a 1?

A. 1/12
B. 1/11
C. 1/10
D. 1/6
E. 1/2


Are You Up For the Challenge: 700 Level Questions


If only one die shows a 1, then the other die can show 5 other numbers and satisfy the condition, for 5 ways.

But, since there are two dice, there are 2*5 = 10 ways for one die to show a 1.

"At least one" means one or more. "Or" means add. So, two dice showing 1 also satisfies the question and of course can happen only

1 way

So, 10+1 = 11 ways to meet the condition. But, only 1 case where both dice show 1, so the probability is

1/11

Posted from my mobile device
User avatar
bumpbot
Non-Human User
Joined: 09 Sep 2013
Posts: 32657
Own Kudos [?]: 821 [0]
Given Kudos: 0
Send PM
Re: A pair of fair six-sided dice is rolled. If at least one of the dice [#permalink] New post   12 Nov 2023, 21:15
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
GMAT Club Bot
gmatclubot
Re: A pair of fair six-sided dice is rolled. If at least one of the dice [#permalink]
12 Nov 2023, 21:15
Moderators:
Bunuel
Math Expert
92900 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions