${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$ reduces acidified ${\text{KMnO}}_4$ into ${\text{Mn}}^{\text{2+}}$ions by releasing ${\text{O}}_2$ gas. In this reaction.          

This is not a redox reaction 

Normality of  ${\text{KMnO}}_{\text{4}}$ is 5 × molarity 

${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}{\text{\hspace{0.17em}and\hspace{0.17em}MnO}}_4^{-}$ react in 1:1 molar ratio

${\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$ and ${\text{MnO}}_4^{-}$react in 5:2 mole ratio