There are c cities. What is the number of airlines that connected 2 different cities (airline from city A to city B is different with airline from city B to city A)? Choose the correct option.
A) c(c-1) B) n(n+1) C) n(n-1)/2 D) n(n+1)/2 E) n2
First of all, the possible number of airlines is c. Then, the possible number of airlines departing from one city to another becomes (c-1). Hence, the answer is c(c-1), c(c-1)
<result>A</result>
There are c cities. What is the number of airlines that connected 2 different cities (airline from city A to city B is different with airline from city B to city A)?