P is a point on the ellipse $\frac{{\mathrm{x}}^2}{36}+\frac{{\mathrm{y}}^2}{9}=1, \mathrm{S}$ and ${\mathrm{S}}^1$ are the foci of the ellipse then $\mathrm{SP}+{\mathrm{S}}^1\mathrm{P}=$

$$\begin{gathered} Given ellipse \frac{x^2}{36}+\frac{y^2}{9}=1 \\ where a^2=36,b^2=9 and a>b \\ Now \mathrm{SP}+{\mathrm{S}}^1\mathrm{P}=2\mathrm{a} \\ =2\left(6\right) \\ =12 \end{gathered}$$