A gaseous fuel $($C$8$H$18)$ is burned in the presence of air that is assumed completely dry. Volumetric analysis of the gaseous products on a dry basis revealed the following composition:

Carbon dioxide $10\%$

Oxygen $5\mathrm{.}6\%$

Carbon monoxide $0\mathrm{.}9\%$

Nitrogen $83\mathrm{.}5\%$

Calculate the air$$to$$fuel ratio