diff --git a/episodes/chap3_run_analysis_ui.md b/episodes/chap3_run_analysis_ui.md
index 36c68957..d9688f87 100644
--- a/episodes/chap3_run_analysis_ui.md
+++ b/episodes/chap3_run_analysis_ui.md
@@ -53,6 +53,33 @@ Given the above, the following are the most important concepts for this lesson:
 - **Result**: the output generated by the execution of an **algorithm** as part of a **task**.
 - **Algorithm**: computational models or processes that are executed on data. Compatible algorithms are those that adhere to the Vantage6 framework, enabling them to be securely distributed to **nodes** for execution.
 
+::::::::::::::::::::::::::::::::::::: challenge
+
+## Mapping vantage6 to "real life"
+Let's imagine a usecase where you would like to study an illness accross
+3 different academic hospitals in the Netherlands: VUmc, Maastricht UMC+, and UMC Utrecht.
+
+You are going to study together with one other person in your group named Daphne.
+
+How would these entities map to your potential usecase?
+
+1. Which organizations would be part of the collaboration?
+2. How many nodes would you run?
+3. How many users would be created?
+
+::::::::::::::::::::::::::::::::::::::::::::::::
+
+:::::::::::::::::::::::: solution
+
+## Solution
+
+1. In this case the organizations would be the academic hospitals as well as your own organization: VUmc, Maastricht UMC+, UMC Utrecht *and* your organization.
+2. One node for every academic hospital, so 3
+3. There will be 2 users running tasks. Additionally there could be more users for administrating the collaboration.
+
+:::::::::::::::::::::::::::::::::
+
+
 ### Where are these concepts in the UI?
 
 After logging in to the vantage6 UI, you will see the start page.
@@ -71,7 +98,7 @@ On the administration page, you can manage the entities of vantage6. The entitie
 
 ::::::::::::::::::::::::::::::::::::: challenge
 
-## Challenge 1: Get familiar with the vantage6 UI
+## Get familiar with the vantage6 UI
 
 Log in to the Vantage6 UI using the credentials below (the password will be given by the instructors). Once logged in, navigate to the administration page to familiarize yourself with the entities there. Then, try to update your email, first name, and last name, but do not change your username, as it will be needed for some of the follow-up challenges.