Thread: Pemutation problem

Hello,

m not sure if this is the right section to post permutation problem, but anyways please help me out with the following

In how many ways can 10 soldiers stand in 2 rows such that there are 5 soldiers in each row?

Is the answer 7257600 or 7257600/2 ?

Puneet

Originally Posted by skyskiers

In how many ways can 10 soldiers stand in 2 rows such that there are 5 soldiers in each row?

It is just
Take any line of ten and divide it into two rows.

Originally Posted by Plato

It is just
Take any line of ten and divide it into two rows.

Yes, you are rig5!ht..it should be 10! , bu was just confused as the text bok says it to be 2*10!

Their logic

10c5 * 5! * 5! * 2

Wouldnt we first divide the line in to groups(equal) of 5 and 5 and the multiply it by 2? As in

10!/(5!)^2 * ( 5!) * (5!) *2 = 10!