A measured temperature on Fahrenheit scale is 200^o F. What will this reading be on celsius scale?

There are three common scales to measure temperature ^oC (degree celsius), ^oF (degree Fahrenheit) and K (Kelvin).
The K is the SI unit.
The temperatures on two scales are related to each other by the following relationship.
${ }^{\mathrm{o}}\mathrm{F}=\frac{9}{5}{\mathrm{t}}^{\mathrm{o}}\mathrm{C}+32$
Putting the values in above equation
$$\begin{gathered} 200-32=\frac{9}{5}{\mathrm{t}}^{\mathrm{o}}\mathrm{C} \\ \Rightarrow \frac{9}{5}{\mathrm{t}}^{\mathrm{o}}\mathrm{C}=168 \\ \Rightarrow {\mathrm{t}}^{\mathrm{o}}\mathrm{C}=\frac{168\times 5}{9}=93.3^{\mathrm{o}}\mathrm{C} \end{gathered}$$