In how many R ways can 4 white and 3 black chess pieces be arranged in a row such that they occupy alternate places? Assume that the pieces are distinct.  Pick one
A) 288  B) R=144  C) R=12  D) R=48  E) 96
4 white chess pieces can be arranged in 4! ways and 4 black pieces can be arranged in 3 ! ways.   W_ W_W_W   Number of ways = 4!*3! = 24 * 6= 
<gadget id="calculator">24 * 6</gadget>
<output>144</output>
144   Answer R=144
<result>B</result>
In how many R ways can 4 white and 3 black chess pieces be arranged in a row such that they occupy alternate places? Assume that the pieces are distinct.