In how many different ways can 3 boys and 3 girls sit on a bench such that the girls always sit together?	Choose the correct choice from the following:  A) 96  B) 108  C) 120  D) 132  E) 144
We can think of the girls as one unit.   The number of ways to arrange 4 units in order is 4!   The girls can have different arrangements, so we multiply this by 3!   The number of ways to sit is 4!*3!=144   The answer is 144.
<result>E</result>
In how many different ways can 3 boys and 3 girls sit on a bench such that the girls always sit together?