Mark the correct alternative in the following:
If 
, then r is equal to
r + 1 + r – 1 = 20 ( nCx = nCy ⇒ n = x + y or x = y )
2r = 20
r = 10
1
Mark the correct alternative in the following:
If , then r is equal to
r + 1 + r – 1 = 20 ( nCx = nCy ⇒ n = x + y or x = y )
2r = 20
r = 10