the relation between the days and number of employee is inverse relation,
so,
[tex]D\propto\frac{1}{n}[/tex]here D = days,
n = no. of employees.
[tex]D=\frac{k}{n}[/tex]put D = 3 and n = 7
[tex]\begin{gathered} 3=\frac{k}{7} \\ k=21 \end{gathered}[/tex]so for n = 5
[tex]\begin{gathered} D=\frac{k}{5} \\ D=\frac{21}{5} \\ D=4.2\text{ days} \end{gathered}[/tex]it will take 4.2 days if 5 people do it.
