multiply the expression by 100 to make it into percentage :
[tex]\begin{gathered} \frac{19}{40\text{ into percenatge }}\text{= 0.475}\times100\text{ } \\ \\ \frac{19}{40\text{ into percenatge }}\text{== 0.475}\times100 \\ \frac{19}{40\text{ into percenatge }}\text{= 47.5\%} \end{gathered}[/tex]Answer : 47.5 %