Answer:
y = 25
Step-by-step explanation:
Given that the quantities are proportional then the equation relating them is
y = kx ← k is the constant of proportion
To find k use the condition y = 10 when x = 6
k = [tex]\frac{y}{x}[/tex] = [tex]\frac{10}{6}[/tex] = [tex]\frac{5}{3}[/tex]
y = [tex]\frac{5}{3}[/tex] x ← equation of proportion
When x = 15, then
y = [tex]\frac{5}{3}[/tex] × 15 = 5 × 5 = 25