I’ve just figuredout what happened here. This question is a simplified version of the Dec 2013 exam q1 ( if you check out that question you’ll see that all numbers are the same but on the exam paper there’s also some data from the SoFP and the £12,000 for RE is given there.
I find it very often in this revision kit that important bits and pieces are missing which makes it very difficult & time consuming to work through the questions. Annoying.