Five spraying machines working together can finish painting a house in $36$ minutes. If $2$ machines break down, then in how much time can the remaining machines complete the job?

If $x$  is in inverse variation with $y$ and $x=4, y=6,$ Find $x$, when $y=12$

If $x$ is in inverse variation with $y$ and

$x=7, y=4,$ Find $y$, when $x=2$

If $x$ is in inverse variation with $y$ and $x=20$, find $y$, when constant of variation is $300$.

If $x$ is in inverse variation with $y$ and $y=16$, find $x$ when constant of variation is $176$.

The quantity of rice sold by two shopkeepers is in the ratio $3 : 5$. If the second shopkeeper sold $25 \mathrm{kg}$ of rice, the quantity of rice sold by the first shopkeeper is: