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

 It is currently 23 Oct 2018, 16:28

### 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

# To announce the winner of a contest, Maria draws from a bowl of raffle

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 50058
To announce the winner of a contest, Maria draws from a bowl of raffle  [#permalink]

### Show Tags

14 Mar 2018, 21:25
1
1
00:00

Difficulty:

45% (medium)

Question Stats:

68% (01:15) correct 32% (01:42) wrong based on 61 sessions

### HideShow timer Statistics

To announce the winner of a contest, Maria draws from a bowl of raffle tickets numbered 1 through 60. What is the probability that the winning number is either even or divisible by 3?

A. 1/2

B. 2/3

C. 3/4

D. 4/5

E. 5/6

_________________
RC Moderator
Joined: 24 Aug 2016
Posts: 401
Concentration: Entrepreneurship, Operations
GMAT 1: 630 Q48 V28
Re: To announce the winner of a contest, Maria draws from a bowl of raffle  [#permalink]

### Show Tags

14 Mar 2018, 21:46
even(A)=30
Div by 3(B)=20
even and div by 3 (A and B) = 10
A or B = A + B - (A and B) = 40
HENCE, P(A or B) =40/60= 2/3------------B
_________________

Please let me know if I am going in wrong direction.
Thanks in appreciation.

Senior PS Moderator
Joined: 26 Feb 2016
Posts: 3207
Location: India
GPA: 3.12
Re: To announce the winner of a contest, Maria draws from a bowl of raffle  [#permalink]

### Show Tags

14 Mar 2018, 23:32
Bunuel wrote:
To announce the winner of a contest, Maria draws from a bowl of raffle tickets numbered 1 through 60. What is the probability that the winning number is either even or divisible by 3?

A. 1/2

B. 2/3

C. 3/4

D. 4/5

E. 5/6

There are a total of 30 even integers in the bowl of raffle tickets.
Also, there are 20 integers which are divisible by 3(out of which
3,9,15,21,27,33,39,45,51,57 are odd and 6,12,18,24,30,36,42,48,54,60 are even)

Since there is an overlap of 10 even integers in both the lists, the total
number of raffle tickets which are either even or divisible by 3 are 30+20-10 = 40

Therefore, the probability that Maria draws the winning number is $$\frac{40}{60} = \frac{2}{3}$$(Option B)
_________________

You've got what it takes, but it will take everything you've got

Manager
Joined: 10 Sep 2015
Posts: 73
Location: India
Concentration: Finance, Human Resources
GMAT 1: 640 Q47 V31
GPA: 4
Re: To announce the winner of a contest, Maria draws from a bowl of raffle  [#permalink]

### Show Tags

15 Mar 2018, 00:26
even elements=30
Elements Divisible by 3 =20
common elements i.e. elements which are both even and div by 3 = 10
so total elemtns that are even or divisible by 3:= 30+20-10=40

P = $$\frac{40}{60}$$ = $$\frac{2}{3}$$

B it is
Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 3906
Location: United States (CA)
Re: To announce the winner of a contest, Maria draws from a bowl of raffle  [#permalink]

### Show Tags

19 Mar 2018, 06:41
1
Bunuel wrote:
To announce the winner of a contest, Maria draws from a bowl of raffle tickets numbered 1 through 60. What is the probability that the winning number is either even or divisible by 3?

A. 1/2

B. 2/3

C. 3/4

D. 4/5

E. 5/6

To find the number of multiples of an integer x in a given interval, we use the formula: (greatest multiple of x - smallest multiple of x)/x + 1

The number of multiples of 2 from 1 to 60, inclusive, is (60 - 2)/2 + 1 = 30.

The number of multiples of 3 from 1 to 60, inclusive, is (60 - 3)/3 + 1 = 20.

We have double-counted the integers that are multiples of both 2 and 3, so we need to subtract out the number of multiples of both 3 and 2 (or the number of multiples of 6).

The number of multiples of 6 from 6 to 60, inclusive, is (60 - 6)/6 + 1 = 10.

Thus, the probability of picking a raffle ticket that is either an even number or a multiple of 3 is (30 + 20 - 10)/60 = 40/60 = 2/3.

_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Re: To announce the winner of a contest, Maria draws from a bowl of raffle &nbs [#permalink] 19 Mar 2018, 06:41
Display posts from previous: Sort by