Answer :
SOLUTION
An inverse variation is given as
[tex]\begin{gathered} a\text{ }\propto\text{ }\frac{1}{b} \\ \text{Introducing a constant k, we have } \\ a\text{ = }\frac{k}{b} \end{gathered}[/tex]Putting a = 10 and b = 2, we have;
[tex]\begin{gathered} 10\text{ = }\frac{k}{2} \\ k\text{ = 10 x 2 = 20 } \end{gathered}[/tex]The relationship becomes
[tex]\begin{gathered} a\text{ = }\frac{20}{b} \\ \text{Putting a = n, and b = 4, we have } \\ n\text{ = }\frac{20}{4} \\ \\ n\text{ = 5} \end{gathered}[/tex]Therefore, n = 5