jalapeno_dude
AKA Panda Judo Eel
I'm sorry, but that's not an adequate answer.The whole order of combat and buying things is done sort of randomly, often depending on the exact tactics people use. Also keep in mind how Carthage and Rome and Egypt spend money on ships too.
updated map
http://forums.civfanatics.com/uploads/32617/UNHjganmg.PNG
-How many new ships did Carthage and Rome recruit?
-The above differences were small enough that it should have taken them some time to defeat the forces already there, especially given that they were in multiple groups.
-I also recruited large numbers of merchant ships into the navy. That shouldn't take any time to accomplish, since new ships were being built.
-Even if all of that didn't occur, what did the 40 triremes do after being built? It would seem likely that they would join up with my still-substantial force and attempt to re-establish naval supremacy. And you don't talk about that at all.