If two integers x, y (x>y) are selected from -10 to 11 (inclusive), how many possible cases are there?
Choose the correct choice from the following
A) 150
B) 180
C) 190
D) 210
E) 231
If two integers x, y (x&gt;y) are selected from -10 to 9 (inclusive), how many possible cases are there?   A. 150   B. 180   C. 190   D. 210   E. 240   --&gt; 22C2=22*21/2= 
<gadget id="calculator">22*21/2</gadget>
<output>231</output>
231. Therefore, the answer is 231.
<result>E</result>
If two integers x, y (x>y) are selected from -10 to 11 (inclusive), how many possible cases are there?