$C=\frac{5}{9}(F-32)$ is a formula that can be used to.
convert from degrees Fahrenheit, $F$, to degrees Celsius, $C$
a) Solve this formula for $F$
b) The average high temperature in Mexico City, Mexico, in April is $25^{\circ} \mathrm{C}$. Use the result in part a) to find the equivalent temperature in degrees Fahrenheit, (www.bbc co.uk)