Pirates

[Jayraj]

On a huge river next to its bank, full of pirates, rests a vessel loaded with treasure.

There are 2 clans of pirate planning to loot that vessel.

The first clan, guided by The Blackbeard, is located 100 feet across the river.

The second, guided by Black Cesear, is founded 100 feet from the vessel along the river bank.

Since there is no access through land to the vessel, the pirates have to sail to the vessel

Both clans have the same type of boats which can travel at 5 feet per second.

The river flows at 3 feet per second.

Which one of them will make the most number of trips before the Rescue Ship arrives?

[ThirdParty]

If I'm reading it correctly, this is a straightforward arithmetic problem.

Spoiler:

Blackbeard's ships make progress at 4 ft/s. (The length of a leg of a right triangle in vector space, whose other leg is the 3 ft/s river and whose hypotenuse is the 5 ft/s ship speed.) So their time to travel 100ft is 25s one-way or 50s round-trip.

Black Cesear's ships make progress at 8 ft/s one direction and 2 ft/s in the other direction, so their 100ft travel times are 12.5s and 50s respectively, for a round-trip travel time of 62.5s.

So Blackbeard's ships will be able to make more round trips.