Answer:
False
Explanation:
Y is inversely proportional to the cube of x. Mathematically, this means
[tex]y\propto\frac{1}{x^3}[/tex]If we now introduce a proportionality constant k, then we get
[tex]y=\frac{k}{x^3}[/tex]Now if y = 5 when x = 2, then
[tex]5=\frac{k}{2^3}[/tex][tex]5=\frac{k}{8}[/tex]Multiplying both sides by 8 gives
[tex]5\times8=k[/tex][tex]\boxed{k=40.}[/tex]Hence, the value of k is NOT 20.
Therefore, the statement that "If Y = 5 when x = 2, then k = 20." is false.
