GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 22 Jan 2019, 02:43

### 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

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

## Events & Promotions

###### Events & Promotions in January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
• ### The winners of the GMAT game show

January 22, 2019

January 22, 2019

10:00 PM PST

11:00 PM PST

In case you didn’t notice, we recently held the 1st ever GMAT game show and it was awesome! See who won a full GMAT course, and register to the next one.
• ### Key Strategies to Master GMAT SC

January 26, 2019

January 26, 2019

07:00 AM PST

09:00 AM PST

Attend this webinar to learn how to leverage Meaning and Logic to solve the most challenging Sentence Correction Questions.

# Is the probability of Arif and Alex, both being present in class, less

Author Message
TAGS:

### Hide Tags

Current Student
Joined: 18 Jan 2017
Posts: 81
Location: India
Concentration: Finance, Economics
GMAT 1: 700 Q50 V34
Is the probability of Arif and Alex, both being present in class, less  [#permalink]

### Show Tags

Updated on: 07 May 2017, 00:35
1
4
00:00

Difficulty:

55% (hard)

Question Stats:

44% (01:08) correct 56% (00:54) wrong based on 40 sessions

### HideShow timer Statistics

Is the probability of Arif and Alex, both being present in class, less than 0.75?

(1) Probability of Alex being present in the class is 0.70
(2) Probability of Arif being present in the class is 0.80

Originally posted by Tan2017 on 07 May 2017, 00:29.
Last edited by Bunuel on 07 May 2017, 00:35, edited 1 time in total.
Edited the question.
Math Expert
Joined: 02 Sep 2009
Posts: 52385
Re: Is the probability of Arif and Alex, both being present in class, less  [#permalink]

### Show Tags

07 May 2017, 00:45
2
Is the probability of Arif and Alex, both being present in class, less than 0.75?

(1) Probability of Alex being present in the class is 0.70. The probability of both Arif and Alex being present cannot be more than individual probabilities any one of them being present. So, P(Arif and Alex) is less than or equal to 0.7. Sufficient.

(2) Probability of Arif being present in the class is 0.80. If P(Alex) = 0, then P(Arif and Alex) is also 0 but if P(Alex) = 1, then P(Arif and Alex) = 0.8. Not sufficient.

_________________
Re: Is the probability of Arif and Alex, both being present in class, less &nbs [#permalink] 07 May 2017, 00:45
Display posts from previous: Sort by