This topic reminds me of those I-banking recruitment questions.

Well, here's my answer about whether delta really has 10,000 routes for sale in the US.

Delta has about 700 US destinations, given they are all linked through the network that is 700^2=490,000 city pairs, well exceeding 10,000.

But, delta won't sell tickets on nearby city route pairs that no one would logically choose to fly. For example BUR-LAX. (check delta.com...can't buy it). How many of these nearby routes could there be? Let's use intra-state city pairs as the benchmark. 48 states in the continental US. Supposing the 700 destinations are uniformly distributed across states results in 700/48=14 illogical destinations for each of the 700 cities in the network. Subtract off 700*14=9800 city pairs, from 490000 gives about 480,000 routes.

There you go, still well over 10,000, even counting out 50 destinations per city be well over 10,000. 10,000 routes would imply a passenger from any given city could only buy tickets to about 14 destinations!! Way to few... Delta marketing folks must be really lousy at math.

[C+ GPA communications major, next in line for the interview, eaves drops and comes up with a quick answer]. FOR SALE...It's a marketing ploy...only 10,000 or about 1/50th of the routes delta offers are for sale. The rest are at full price.

Which guy gets the I-banking job?