A meeting has to be conducted with 3 managers. Find the number of ways in which the managers be selected from among 6 managers, if 2 managers will not attend the meeting together?
Choose the correct choice from the following: A) 18 B) 20 C) 16 D) 22 E) 24
we can either choose all 3 people from 4 manager who have no problems or choose 2 from the 4 and 1 from the 2 managers who have a problem sitting together   so 4163 + (4162 * 2161)   this is   4 + 12= 
<gadget id="calculator">  4 + 12</gadget>
<output>16</output>
16   Answer : 16
<result>C</result>
A meeting has to be conducted with 3 managers. Find the number of ways in which the managers be selected from among 6 managers, if 2 managers will not attend the meeting together?