The variable z is directly proportional to x, and inversely proportional to y. When x is 7 and y is 7, z has the value 2. What is the value of z when x= 10, and y= 12

Respuesta :

Answer:

z = [tex]\frac{5}{3}[/tex]

Step-by-step explanation:

Given z is directly proportional to x and inversely proportional to y then the equation relating them is

z = [tex]\frac{kx}{y}[/tex] ← k is the constant of proportionality

To find k use the condition x = 7, y = 7 and z = 2

k = [tex]\frac{zy}{x}[/tex] = [tex]\frac{2(7)}{7}[/tex] = 2

z = [tex]\frac{2x}{y}[/tex] ← equation of proportionality

When x = 10 and y = 12, then

z = [tex]\frac{2(10)}{12}[/tex] = [tex]\frac{20}{12}[/tex] = [tex]\frac{5}{3}[/tex]