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budetta4: Junior | Next Rank: 30 Posts; Posts: 20; Joined: Tue Nov 10, 2009 9:06 am

by budetta4 » Wed Feb 17, 2010 2:59 am

if 3 boys and three girls must sit in a row of six chair but neither boys or girls are allowe to sit, how many different seating arrangemets can be made?

A 12
B 36
C72
D 180
E 360

could spmeone explain me how to solve it?

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Source: Beat The GMAT — Problem Solving | Wed Feb 17, 2010 2:59 am

sadullaevd: Senior | Next Rank: 100 Posts; Posts: 81; Joined: Wed Apr 08, 2009 3:12 pm; Location: South Korea; Thanked: 4 times

by sadullaevd » Wed Feb 17, 2010 3:04 am

could you plz check question stem,

i cant understand it, guess others will also find it unclear.

thank you.

Stay skeptical,
Think critically,
Assume nothing.

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papgust: Community Manager; Posts: 1537; Joined: Mon Aug 10, 2009 6:10 pmFollowed by: 252 members; Thanked: 653 times

by papgust » Wed Feb 17, 2010 3:05 am

Can you check the question? It doesn't sound logical. First, it says that boys and girls must in a row, but then it says that neither boys nor girls are allowed to sit.

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thephoenix: Legendary Member; Posts: 1560; Joined: Tue Nov 17, 2009 2:38 amFollowed by: 5 members; Thanked: 137 times

by thephoenix » Wed Feb 17, 2010 3:13 am

budetta4 wrote:if 3 boys and three girls must sit in a row of six chair but neither boys nor girls are allowed to sit together, how many different seating arrangemets can be made?

A 12
B 36
C72
D 180
E 360

could spmeone explain me how to solve it?

i guess the question is like the abve one

if yes than IMO B sud be the ans

3 boys can be placed in 3!=6 ways
in b/n three places 3 girls can seated in 3!=6 ways
tot=6*6=36

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ajith: Legendary Member; Posts: 1275; Joined: Thu Sep 21, 2006 11:13 pmFollowed by: 2 members; Location: Arabian Sea; Thanked: 125 times

by ajith » Wed Feb 17, 2010 3:31 am

budetta4 wrote:if 3 boys and three girls must sit in a row of six chair but neither boys or girls are allowed to sit together, how many different seating arrangements can be made?

A 12
B 36
C72
D 180
E 360

could someone explain me how to solve it?

_ _ _ _ _

We can either arrange boys in 1st , 3rd and 5th slot , or 2nd, 4th and 6th slot
Boys can be arranged within themselves in 6 ways
Girls can be arranged within themselves in 6 ways

Total no of ways = 2*6*6 = 72

C

Always borrow money from a pessimist, he doesn't expect to be paid back.

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