Wind chill is a measure of how cold people feel when exposed to wind outside

MATHEMATICS · Numerical · GCSE · Mathematics · Ratio and Proportion · Ratio and Proportion

Problem

Wind chill is a measure of how cold people feel when exposed to wind outside. A good estimate for wind chill is

\text{wind chill}=\text{air temperature}-0.7\times\text{wind speed},

where temperature is measured in degrees Fahrenheit

({}^{\circ}\mathrm{F})

and wind speed is measured in miles per hour

({}\mathrm{mph})

. Suppose the air temperature is

36{}^{\circ}\mathrm{F}

and the wind speed is

18\,\mathrm{mph}

. Find the approximate wind chill.