Screens are a measure of the diagonal of the box. As you can notice in the following image:
The hypotenuse h determines the size of the screen. Use the Pythagoras theorem to find the value of h, as follow:
[tex]\begin{gathered} h^2=(15)^2+(27)^2 \\ h^2=954 \\ h=\sqrt[]{954}\approx30.98 \end{gathered}[/tex]
Hence, the size of the screen would be approximately 30.98 inches
