# Math Help - Pemutation problem

1. ## 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

2. 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 $10!=3628800$
Take any line of ten and divide it into two rows.

3. Originally Posted by Plato
It is just $10!=3628800$
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!