prob

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 113
Joined: Mon Apr 26, 2010 8:58 am
Thanked: 2 times
Followed by:14 members

prob

by divya23 » Thu Jun 02, 2011 9:42 pm
cake manufacture of cake, muffin and bread has 100 buyers
50 purchase cakes
40 = muffin
and 20 = cake and muffin both
if a buyer is to be selected form 100 buyers what is the probability that the buyer selected will be one hu purchases neither cake nor muffin
1/10
3/10
1/2
7/10
9/10

3/10
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pm
Location: Milpitas, CA
Thanked: 1854 times
Followed by:523 members
GMAT Score:770

by Anurag@Gurome » Thu Jun 02, 2011 9:50 pm
Number of buyers who purchases only cake = C = (50 - 20) = 30
Number of buyers who purchases only muffin = M = (40 - 20) = 20
Number of buyers who purchases both of them = CM = 20
Number of buyers who purchases neither of them = N

Now, total number of buyers = (C + M + CM + N) = 100

Hence, N = 100 - (C + M + CM) = 100 - (30 + 20 + 20) = 30

Required Probability = 30/100 = 3/10

The correct answer is B.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/

User avatar
Legendary Member
Posts: 1309
Joined: Mon Apr 04, 2011 5:34 am
Location: India
Thanked: 310 times
Followed by:123 members
GMAT Score:750

by cans » Thu Jun 02, 2011 9:59 pm
total 100
c=50
m=40
both=20
Thus only cake=50-20=30
only muffin = 40-20=20
total = only cake + only muffin + both + none
=> none = 100-30-20-20 = 30
prob = 30/100 = 3/10
IMO B
If my post helped you- let me know by pushing the thanks button ;)

Contact me about long distance tutoring!
[email protected]

Cans!!