5. Calculate: $8.0 \dot{\dot{1}}+7.1 \dot{2}+6.2 \dot{3}+5.3 \dot{4}+4.4 \dot{5}+3.5 \dot{6}+2.6 \dot{7}+1.7 \dot{8}=$
Reference answer: 39.2

Exam point: Simplified calculation -- calculation of recurring decimals