There are 7 couples. If they will sit 14 chairs in a row such that each couple sits side by side, how many possible cases are there?	Choose one: A) 120 B) 240 C) 1,200 D) 2,460 E) 654120
Tie the couples. Then we have 5 persons that have to be arranged in 4 places. 4! ways.   Now the couples can change position with each other. 2! ways.   7! * (2!)^7=5040 *128= 
<gadget id="calculator">5040 *128</gadget>
<output>645_120</output>
645120   Answer is 654120.
<result>E</result>
There are 7 couples. If they will sit 14 chairs in a row such that each couple sits side by side, how many possible cases are there?