Answer: They controlled the seas together.
Step-by-step explanation: The Triple Entente was composed by an alliance between The United Kingdom of Britain and Ireland, The Russian Empire and The French Third Republic. These three entities did not share the same seas or boarders and did not have a centralized location as opposed to their enemy, The Triple Alliance, integrated by The German Empire, The Austria-Hungary Empire and Italy, countries who actually did share boarders. The Russian Empire collided with the Baltic Sea to the northwest and the Black Sea to the south; The French Third Republic collided with Mediterranean Sea to the south and the Atlantic Ocean to the north; The United Kingdom Collided with the Atlantic Ocean to the west and the North Sea to the east.
What actually was an advantage of the Triple Entente over the Triple Alliance was the fact that, whilst surrounding their enemies, they were able to control all those seas and narrow straits together freely.