Answer:
y = 28
Step-by-step explanation:
Given that y varies directly as x and inversely as z then the equation relating them is
y = [tex]\frac{kx}{z}[/tex] ← k is the constant of variation
To find k use the condition y = 4 when x = 2 and z = 7, then
4 = [tex]\frac{2k}{7}[/tex] ( multiply both sides by 7 )
28 = 2k ( divide both sides by 2 )
14 = k
y = [tex]\frac{14x}{z}[/tex] ← equation of variation
When x = 6 and z = 3 , then
y = [tex]\frac{14(6)}{3}[/tex] = 14 × 2 = 28