# permutation and combination

• January 8th 2013, 06:07 AM
permutation and combination
here is the question: eight people sit in a minibus four on the sunny side and four on the shady side. if 2 people want to sit on opposite sides to each other and another 2 people want to sit on the shady side in how many ways can this be done ??
• January 8th 2013, 08:12 AM
Plato
Re: permutation and combination
Quote:

Originally Posted by arshad2468
here is the question: eight people sit in a minibus four on the sunny side and four on the shady side. if 2 people want to sit on opposite sides to each other and another 2 people want to sit on the shady side in how many ways can this be done ??

I assume that there only eight seats. So there only $8$ ways to seat the couple opposite each other. WHY?

There are then $3\cdot 2$ ways to seat the other two people on the sunny side. Can you explain that?

How many seats remain and how many ways can they be occupied?
• January 8th 2013, 08:46 PM
Re: permutation and combination
how will u do it then?? that's the question
• January 9th 2013, 04:46 AM
Plato
Re: permutation and combination
Quote:

Originally Posted by arshad2468
how will u do it then?? that's the question

You read reply #2 and answer the questions written there?
• January 9th 2013, 07:02 AM
HallsofIvy
Re: permutation and combination
Quote:

Originally Posted by arshad2468
how will u do it then?? that's the question

No, it's not. The question is how will you do it. Plato has given some good hints on how to start. Now, you some interest in the problem to show that it is worth our time to help.