Answer:
y = 18
Step-by-step explanation:
Given y varies directly as x then the equation relating them is
y = kx ← k is the constant of variation
To find k use the condition y = 28 when x = 168
28 = 168k ( divide both sides by 168 )
[tex]\frac{28}{168}[/tex] = k , that is
k = [tex]\frac{1}{6}[/tex]
y = [tex]\frac{1}{6}[/tex] x ← equation of variation
When x = 108 , then
y = [tex]\frac{1}{6}[/tex] × 108 = 18
