Deriving rules for block diagram reduction:
https://youtu.be/74ky47hKGoM
Solving this problem with a different method:
https://youtu.be/8qJRiNkACVI
Please note that there are many different ways to solve this kind of problem, and this is just one of them. If you followed different steps and arrived at the the same answer, your solution is probably correct as well.
Timestamps:
0:00 - Problem introduction
0:38 - Block diagram reduction
9:11 - Answer
If you have any questions or want to see me make a video about something, please leave a comment below!