Answer
Find out the what is the value of x when y = 8 .
To prove
As given
The variables y and x have a proportional relationship.
[tex]y \propto x[/tex]
y = kx
Where k is the constant of proportionality.
As y = 5 when x = 4
Put in the above
5 = 4k
[tex]k = \frac{5}{4}[/tex]
Now find out the value of x , when y = 8
[tex]8 = \frac{5\times x}{4}[/tex]
[tex]x = \frac{8\times 4}{5}[/tex]
x= 6.5
Therefore when y = 8 than x = 6.4
