Eighteen  guests are to  be seated, half on  each side  of a long table. Four particular guests desire to sit  on one particular side and  three on other side of the table .Find the  number of ways  in which the seating arrangement  can be  made .

After seating  4 on one side  and 3 on the other side we have to seletct out  of 11.5 on one side and 6 on the other side 
Now, there are 9 on each side  of  the long table  and  each cannot  be arranged  in 9! Ways 
The  number ways  in which the  seating arrangement can be  made = $\frac{11!}{5!6!}(9!)(9!)$