What is the proportion equivalent to $\frac{X}{Y} : \frac{Y}{Z} : \frac{X}{Z}$, if $X : Y : Z = 4 : 7 : 9$?
Answer & explanation
Correct answer: option 4
\(\frac{X}{Y}\) : \(\frac{Y}{Z}\) : \(\frac{X}{Z}\)
⇒ \(\frac{4}{7}\) : \(\frac{7}{9}\) : \(\frac{4}{9}\)
⇒ Taking LCM of denominators as 63, therefore
⇒ 9 x 4 : 7 x 7 : 7 x 4
⇒ 36 : 49 : 28