1) 8.2+(8.2*(20% : 100%))=8.2+(8.2*0.2)=8.2+1.64=9.84
8.2-(8.2*(2% : 100%))=8.2-(8.2*0.02)=8.2-0.164=8.036
2)11.5+(11.5*(16% : 100%))=11.5+(11.5*0.16)=11.5+1.84=13.34
11.5+(11.5*(3.8% : 100%))=11.5+(11.5*0.038)=11.5+0.437=11.937
3)6.2-(6.2*(12% : 100%))=6.2-(6.2*0.12)=6.2-0.744=5.456
6.2+(6.2*(5% : 100%))=6.2+(6.2*0.05)=6.2+0.31=6.51