$\begin{matrix}\:\:&2&1&.&7&\bold{5}\\+&0&2&.&2&\bold{8}\end{matrix}$
Carry $1$ to the column on the left and write $3$ in the bolded column$\frac{\begin{matrix}\:\:&\:\:&\:\:&\:\:&1&\bold{\:\:}\\\:\:&2&1&.&7&\bold{5}\\+&0&2&.&2&\bold{8}\end{matrix}}{\begin{matrix}\:\:&\:\:&\:\:&\:\:&\:\:&\bold{3}\end{matrix}}$
Add the digits of the bolded column $1+7+2=10$$\frac{\begin{matrix}\:\:&\:\:&\:\:&\:\:&\bold{1}&\:\:\\\:\:&2&1&.&\bold{7}&5\\+&0&2&.&\bold{2}&8\end{matrix}}{\begin{matrix}\:\:&\:\:&\:\:&\:\:&\bold{\:\:}&3\end{matrix}}$
Carry $1$ to the column on the left and write $0$ in the bolded column$\frac{\begin{matrix}\:\:&\:\:&1&\:\:&\bold{1}&\:\:\\\:\:&2&1&.&\bold{7}&5\\+&0&2&.&\bold{2}&8\end{matrix}}{\begin{matrix}\:\:&\:\:&\:\:&\:\:&\bold{0}&3\end{matrix}}$
Place the decimal point in the answer directly below the decimal points in the terms$\frac{\begin{matrix}\:\:&\:\:&1&\bold{\:\:}&1&\:\:\\\:\:&2&1&\bold{.}&7&5\\+&0&2&\bold{.}&2&8\end{matrix}}{\begin{matrix}\:\:&\:\:&\:\:&\bold{.}&0&3\end{matrix}}$
Add the digits of the bolded column $1+1+2=4$$\frac{\begin{matrix}\:\:&\:\:&\bold{1}&\:\:&1&\:\:\\\:\:&2&\bold{1}&.&7&5\\+&0&\bold{2}&.&2&8\end{matrix}}{\begin{matrix}\:\:&\:\:&\bold{4}&.&0&3\end{matrix}}$
Add the digits of the bolded column $2+0=2$$\frac{\begin{matrix}\:\:&\bold{\:\:}&1&\:\:&1&\:\:\\\:\:&\bold{2}&1&.&7&5\\+&\bold{0}&2&.&2&8\end{matrix}}{\begin{matrix}\:\:&\bold{2}&4&.&0&3\end{matrix}}$
Write the numbers one under the other, line up the decimal points. $$\begin{matrix}\:\:&2&1&.&7&5\\+&0&2&.&2&8\end{matrix}$ $=24.03$