https://www.gamespot.com/articles/fortnite-where-to-complete-timed-trials-week-6-sea/1100-6461200/

The weekly challenges for Fortnite have been refreshed on PS4, Xbox One, PC, Nintendo Switch, and mobile, which means there's a new batch of Battle Stars to be earned. We've already put together a guide to all the Week 6 and Week 7 challenges, including a walkthrough of how to complete the Search Where The Stone Heads Are Looking challenge. However, there's a second challenge in the Week 6 batch that is a little more difficult than the rest--complete timed trials. But never fear, we've got some tips that will help you through it.

The challenge is exclusive to the paid Battle Pass tier and asks players to complete five timed trials. This is the first challenge of its kind and involves collecting a number timer symbols within a certain location before the allotted time runs out. This is pretty easy on its own, but it's not simply a case of running to them and grabbing them. Some of the timed trials are much easier if you build your way up to the collectible, so you'll need to have resources handy. Others, meanwhile, can be done quicker by using an ATK, which doesn't automatically spawn nearby, so you'll have to hunt for one.