Priya uses 24 drops of red dye,
She also uses 16 drops of blue dye,
[tex]\begin{gathered} \text{Total drops of dye=}24+16 \\ =40\text{drops of dye} \end{gathered}[/tex]We are told to find the ratio of drops of red dye to the total drops dye.
[tex]=\frac{\text{red drops of dye}}{\text{total drops of dye}}[/tex][tex]\begin{gathered} =\frac{24}{40}=\frac{3}{5} \\ =3\colon5 \end{gathered}[/tex]Hence, the ratio of drops of red die to the total drops of die to the simplest rato is
3 : 5.