@danilang - This is the second time in a month I've realized (far too late) that the Make Groups tool could have been extremely efficient & useful. Underappreciated Alteryx tools for the win!! Well done reading the instructions - I should probably try that sometime haha.
I'll challenge you on the not following instructions part. The hint was "You will make 5 groups", not "use the Make Groups tool". I'm not going to feel too bad if I solution like @NicoleJohnson as I was inspired to start working through the weekly challenges by watching her win the 2018 Grand Prix.