Because Z is directly proportional to X and inversely proportional to Y, therefore
[tex]Z=k \frac{X}{Y} [/tex]
where k = constant.
When X = 15 and Y = 9, Z = 5. Therefore
k(15/9) = 5
k = 5*(9/15) = 3
That is,
[tex]Z= \frac{3X}{Y} [/tex]
When X = 23, and Y = 14, obtain
Z = (3*23)/14 = 4.9286
Answer: Z = 4.929 (nearest thousandth)
