Question

Find the mean proportional between 0.3 and 2.7

• A. 0.03
• B. 0.9
• C. 0.09
• D. 0.81

Answer 1

The correct option is B

0.9

Let $b$ be the mean proportional , then we have $a:b::b:c$ are in proportion

$\therefore$ $b^2$ = $a\times c$ (Given a = 0.3, c = 2.7)

= $0.3\times 2.7$

= 0.81

$b=\sqrt{0.81}$

= 0.9

Hence mean proportion of 0.3 and 2.7 is 0.9