Two members of a certain club are selected to speak at the next club meeting. If there are 36 different possible selections of the 2 club members, how many members does the club have?
Choose the most appropriate option.
A) 5
B) 6
C) 7
D) 8
E) 9
Let, Total members = n   @n=2, no. of ways to select 2 out of 2(A,B) = (AB) = 1   @n=3, no. of ways to select 2 out of 3(A,B,C) = (AB, AC, BC) = 2+1= 
<gadget id="calculator">2+1</gadget>
<output>3</output>
3   @n=4, no. of ways to select 2 out of 4(A,B,C,D) = (AB, AC, AD, BC, BD, CD) = 3+2+1= 
<gadget id="calculator">3+2+1</gadget>
<output>6</output>
6   i.e. @n=5, Total Selection of 2 = 4+3+2+1= 
<gadget id="calculator">4+3+2+1</gadget>
<output>10</output>
10   i.e. @n=6, Total Selection of 2 = 5+4+3+2+1= 
<gadget id="calculator">5+4+3+2+1</gadget>
<output>15</output>
15   i.e. @n=7, Total Selection of 2 = 6+5+4+3+2+1= 
<gadget id="calculator">6+5+4+3+2+1</gadget>
<output>21</output>
21   i.e. @n=8, Total Selection of 2 = 7+6+5+4+3+2+1= 
<gadget id="calculator">7+6+5+4+3+2+1</gadget>
<output>28</output>
28   i.e. @n=9, Total Selection of 2 = 8+7+6+5+4+3+2+1= 
<gadget id="calculator">8+7+6+5+4+3+2+1</gadget>
<output>36</output>
36   Answer: Option 9
<result>E</result>
Two members of a certain club are selected to speak at the next club meeting. If there are 36 different possible selections of the 2 club members, how many members does the club have?