Find the ratio between the 3rd proportional of 2.9 & 3.6 and the 4th proportional of 1.45, 2.4 & 7.2.

3 : 8

3rd proportional of a & b = \(\frac{b^2}{a}\),

4th proportional of a,b & c = \(\frac{bc}{a}\)

ATQ, Ratio will be:

⇒ \(\frac{3.6\;×\;3.6}{2.9}\) : \(\frac{2.4\;×\;7.2}{1.45}\) ⇒ \(\frac{36\;×\;36}{290}\) : \(\frac{24\;×\;72}{145}\) ⇒ 3: 8