Wow I don't get it either but my guess would be 9,6...sorry....
3 2/5 3•5+2 17/5 3.4 11 3/20 223/20 11.15 +3.4=11.15
-3.4 -3.4
= 7.75
7.75+3.6 11.15
11.15=11.15
A) the middle of the range is 39.5%
b) the difference between the middle and the ends of the range is ±1.5%
c) less than a majority favor change. Change seems unlikely.