SSC CPO SI and ASI Model Paper 3

(1) Total marks of 5 students whoscored 100 marks each = 5 × 100= 500
Total marks of 6 students whoscored 2 marks each = 6 × 2 = 12Remaining students = 25 – (5 + 6)= 14
Sum of marks of 14 studentswhose average marks are 20 = 14× 20 = 280
Average marks of whole class =
$\frac{\mathit{S}\mathit{u}\mathit{m}\mathit{o}\mathit{f}\mathit{m}\mathit{a}\mathit{r}\mathit{k}\mathit{s}\mathit{o}\mathit{b}\mathit{t}\mathit{a}\mathit{i}\mathit{n}\mathit{e}\mathit{d}\mathit{b}\mathit{y}25\mathit{s}\mathit{t}\mathit{u}\mathit{d}\mathit{e}\mathit{n}\mathit{t}\mathit{s}}{\mathit{T}\mathit{o}\mathit{t}\mathit{a}\mathit{l}\mathit{n}\mathit{u}\mathit{m}\mathit{b}\mathit{e}\mathit{r}\mathit{o}\mathit{f}\mathit{s}\mathit{t}\mathit{u}\mathit{d}\mathit{e}\mathit{n}\mathit{t}\mathit{s}}$
$=\frac{500+12+280}{25}$
$=\frac{792}{25}=31.68$marks