Question

The variable Z is directly proportional to X. When X is 3, Z has the value 54. What is the value of Z when X = 12

Answer 1

Given that z is directly proportional to x, then:
zαx
hence;
z=kx
therefore:
k=z/x
when x=3,z=54
thus;
k=54/3
=18
hence;
z=18x
therefore the value of z when x=12 will be:
z=18*12
z=216
The answer is z=216