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

 It is currently 16 Jan 2019, 16:39

### 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 winning strategy for a high GRE score

January 17, 2019

January 17, 2019

08:00 AM PST

09:00 AM PST

Learn the winning strategy for a high GRE score — what do people who reach a high score do differently? We're going to share insights, tips and strategies from data we've collected from over 50,000 students who used examPAL.
• ### Free GMAT Strategy Webinar

January 19, 2019

January 19, 2019

07:00 AM PST

09:00 AM PST

Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.

# A study found that 80% of drivers, who ride with a passenger, wear sea

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 52161
A study found that 80% of drivers, who ride with a passenger, wear sea  [#permalink]

### Show Tags

30 Jan 2018, 07:05
00:00

Difficulty:

15% (low)

Question Stats:

85% (02:08) correct 15% (02:03) wrong based on 58 sessions

### HideShow timer Statistics

A study found that 80% of drivers, who ride with a passenger, wear seatbelts. Passengers wear seatbelts 70% of the time when the driver wears a seatbelt, and 55% of the time when the driver doesn't wear a seatbelt. What is the probability that a passenger wears a seatbelt?

A. 11%
B. 33%
C. 56%
D. 67%
E. 80%

_________________
Senior Manager
Joined: 17 Oct 2016
Posts: 318
Location: India
Concentration: Operations, Strategy
GPA: 3.73
WE: Design (Real Estate)
Re: A study found that 80% of drivers, who ride with a passenger, wear sea  [#permalink]

### Show Tags

30 Jan 2018, 07:21
1
D

lets say there are 100 drivers and 100 passengers.

80 driver wear seatbelts and 20 dont.

70% passengers wear seatbelt when the driver wears seatbelt. i.e 80*0.7=56 passengers wear seatbelt

55% passengers wear seatbelt when the driver doesn''t wear seatbelt. i.e 20*0.55=11 passengers wear seatbelt

so on a total 56+11 =67 passengers wear seatbelt. Hence 67%
_________________

Help with kudos if u found the post useful. Thanks

e-GMAT Representative
Joined: 04 Jan 2015
Posts: 2438
Re: A study found that 80% of drivers, who ride with a passenger, wear sea  [#permalink]

### Show Tags

31 Jan 2018, 00:08
Bunuel wrote:
A study found that 80% of drivers, who ride with a passenger, wear seatbelts. Passengers wear seatbelts 70% of the time when the driver wears a seatbelt, and 55% of the time when the driver doesn't wear a seatbelt. What is the probability that a passenger wears a seatbelt?

A. 11%
B. 33%
C. 56%
D. 67%
E. 80%

Solution

Thus, the correct answer is Option D.

Regards,
Saquib
Quant Expert
e-GMAT
_________________

Number Properties | Algebra |Quant Workshop

Success Stories
Guillermo's Success Story | Carrie's Success Story

Ace GMAT quant
Articles and Question to reach Q51 | Question of the week

Number Properties – Even Odd | LCM GCD | Statistics-1 | Statistics-2 | Remainders-1 | Remainders-2
Word Problems – Percentage 1 | Percentage 2 | Time and Work 1 | Time and Work 2 | Time, Speed and Distance 1 | Time, Speed and Distance 2
Advanced Topics- Permutation and Combination 1 | Permutation and Combination 2 | Permutation and Combination 3 | Probability
Geometry- Triangles 1 | Triangles 2 | Triangles 3 | Common Mistakes in Geometry
Algebra- Wavy line | Inequalities

Practice Questions
Number Properties 1 | Number Properties 2 | Algebra 1 | Geometry | Prime Numbers | Absolute value equations | Sets

| '4 out of Top 5' Instructors on gmatclub | 70 point improvement guarantee | www.e-gmat.com

Director
Joined: 31 Jul 2017
Posts: 516
Location: Malaysia
GMAT 1: 700 Q50 V33
GPA: 3.95
WE: Consulting (Energy and Utilities)
Re: A study found that 80% of drivers, who ride with a passenger, wear sea  [#permalink]

### Show Tags

08 Feb 2018, 01:35
Bunuel wrote:
A study found that 80% of drivers, who ride with a passenger, wear seatbelts. Passengers wear seatbelts 70% of the time when the driver wears a seatbelt, and 55% of the time when the driver doesn't wear a seatbelt. What is the probability that a passenger wears a seatbelt?

A. 11%
B. 33%
C. 56%
D. 67%
E. 80%

Total probability = 0.8(When the Driver wears seat belt)*0.7(When the Passenger wears seat belt) + 0.2(When the Driver doesn't wear seat belt)*0.7(When the Passenger wears seat belt) = 0.67
_________________

If my Post helps you in Gaining Knowledge, Help me with KUDOS.. !!

Re: A study found that 80% of drivers, who ride with a passenger, wear sea &nbs [#permalink] 08 Feb 2018, 01:35
Display posts from previous: Sort by