Question

Mean proportional between 7 and 28 is

• A. 14
• B. 12
• C. 16
• D. 17

Answer 1

The correct option is A 14

solution :

for mean proportion

$\frac{a}{x}=\frac{x}{b}$

$x^2=a$ x $b$

$x=\sqrt{7x28}$

$x=\sqrt{196}$

$x=14$

hence the correct opt: A