correct, I am not saying the step 5. I mean the bonus. it should use step 4’s expected score(1.6) to calculate the bonus not step 5(2.08) based on the doc:
E = 1.6
K(S−E)=36⋅(3−1.600)=36⋅1.400=50.4
Bm′=10⋅5≈22.36
Bonus=max(0,50.4−22.36)≈28.0
but systems gives 11.