For the following molecules:

calculate the value of  
a = Number of species having $s{p}^3$ d-hybridization
b = Number of species which are planar
c = Number of species which are non – planar

$$\begin{gathered} PC{l}_5\to s{p}^{3}d,non-planar Br{F}_3\to s{p}^{3}d,bent,T-shapeplanar \\ IC{l}_2^{-}\to s{p}^{3}d,linear,planar Xe{F}_5^{-}\to s{p}^3{d}^3,pentagonalplanar \\ Xe{O}_2{F}_2\to s{p}^{3}d,see-saw,non-planar PC{l}_4^{+}\to s{p}^3,tetrahedral,non-planar \\ C{H}_3^{+}\to s{p}^2,trigonalplanar a=4,b=5,c=3 so,\frac{a+b}{c}=3 \end{gathered}$$