Let the constant of variation be c.
We are given that y varies inversely with 2.5x, this means that:
y = (c) / (2.5x)
This can be written as:
2.5xy = c
Now, we a re given that y = 5.6 at x = 30.
Substitute with these values in the equation to get the value of c as follows:
2.5xy = c
2.5(30)(5.6) = c
c = 420
Therefore, the equation that describes the relation is:
2.5xy = 420
