Answer:
z = 3.6
Step-by-step explanation:
Given that,
z varies directly with x and inversely with the square of y. We can write it as :
[tex]z\propto \dfrac{x}{y}\\\\z=\dfrac{kx}{y}[/tex]
Where
k is constant
Put z = 16 when x = 4 and y = 1
[tex]16=\dfrac{k\times 4}{1}\\\\k=4[/tex]
Now put k = 4, x = 8 and y = 9
[tex]z=\dfrac{4\times 8}{9}\\\\z=3.6[/tex]
So, the value of z is equal to 3.6.