Question

(b) Find the value of 'x' is the following are in continued proportion.

(i)25,x, 49

please tell urgent ​

Answer 1

ANSWER:

Given:

• 25, x, 49 are in continued proportion.

To Find:

• Value of x

Solution:

$\text{As, 25, x, and 49 are in continued proportion,}\\\\:\longrightarrow 25 : x :: x : 49\\\\:\implies 25 : x=x : 49\\\\\text{So,}\\\\:\implies\dfrac{25}{x}=\dfrac{x}{49}\\\\\text{On cross multiplying,}\\\\:\implies 25\times49=x \times x\\\\:\implies x^2=25\times49\\\\:\implies x=\sqrt{25\times49}\\\\:\implies x=\sqrt{(5^2)\times(7^2)}\\\\:\implies x=\sqrt{(5\times7)^2}\\\\:\implies x=5\times7\\\\\bf{:\implies x=35}$

Formula Used:

• Continued proportion ⇒ a : b :: b : c
• a² × b² = (ab)²