What is the difference in the mean proportional between 1.8 and 3.2 and the third proportional to 5 and 3?
Answer & explanation
Correct answer: option 4
Formula for mean proportion of A, B = $\sqrt{A\;\times\;B}$
Mean proportion of 1.8 and 3.2 = \(\sqrt {1.8\; \times\; 3.2}\)
= 2.4
Formula for third proportion of A, B = $\frac{B\;\times\;B}{A}$
Third proportion of 5 and 3 = \(\frac{3\; \times\; 3}{5}\)
= \(\frac{9}{5}\) = 1.8
Difference between them = 2.8 - 1.8 = 0.6