NIFT UG 2019 Question Paper with solutions

Let the time for which man travels on foot $=\mathit{x}$ h
Then, the time for which man travels on bicycle
$=\left(7-\mathit{x}\right)\mathit{h}$
Now, according to the question,
$8\times \mathit{x}+16\left(7-\mathit{x}\right)=80$
$[\because$ Distance $=$ Speed $\times$ Time $]$
$\Rightarrow 8\mathit{x}+112-16\mathit{x}=80$
$\Rightarrow -8\mathit{x}=-112+80\Rightarrow 8\mathit{x}=32$
$\Rightarrow \mathit{x}=\frac{32}{8}=4$
$\therefore$ Distance covered on foot $=8\times 4=32\mathit{k}\mathit{m}$