Question

The variable Z is directly proportional to X. When X is 12, Z has the value 228.

What is the value of Z when X = 18

Answer 1

\(x=zk\)

\(12=228*k \implies k=\frac{12}{228}\)

So \(x=z*\frac{12}{228}\)

Plug in \(x=18\) to find the corresponding \(z\)

Answer 2

@zz0ck3r The stated relationship between the variable Z and the variable X can be expressed as:
Z = kX. This seems to be clearer than X = kZ. Simply because the problem does not state that X is directly proportional to Z. Although obviously it would have to be.