Answer:
4.5
Step-by-step explanation:
→ Set up the direct proportion equation
z = kx
→ Substitute in the values
12 = 3k
→ Divide both sides by 3 to isolate k
4 = k
→ Substitute the value of k back into the original direct proportion equation
z = 4x
→ Substitute the value of z in
18 = 4x
→ Divide both sides by 4 to isolate x
4.5 = x
