if two integers x , y ( x > y ) are selected from - 10 to 11 ( inclusive ) , how many possible cases are there ?
"if two integers x , y ( x > y ) are selected from - 10 to 9 ( inclusive ) , how many possible cases are there ? a . 150 b . 180 c . 190 d . 210 e . 240 - - > 22 c 2 = 22 * 21 / 2 = 231 . therefore , the answer is e ."
add(add(add(add(add(add(add(11, 10), add(11, const_2)), add(11, const_1)), 11), 10), const_2), const_1)