Question

In countries like USA and Canada temperature is measured in Fahrenheit where as in countries like India, it is measured in Celsius. Here is a liner equation that converts Fahrenheit to Celsius $F=\left(\frac{9}{5}\right)C+32$ If the temperature is 30${}^o$ C, what is the temperature in Fahrenheit?

Answer 1

Given $F=\frac{9}{5}C+32$

Divided by $\frac{5}{9}$ both side we get

$F\times \frac{5}{9}=\frac{9}{5}C\times \frac{5}{9}+32\times \frac{5}{9}$

$\Rightarrow \frac{5}{9}F=C+\times \frac{5}{9}\times 32$

$\Rightarrow C=\frac{5}{9}F-\frac{5}{9}\times 32$

$\Rightarrow C=\frac{5}{9}(f-32)$

$F=\frac{9}{5}C+32$

$F=\frac{9}{5}\times 30+32=54+32=86$