Find the value of (√1.69 + √0.49) × √400 :

Correct option is D

Given:

We need to evaluate the expression:
​$$(\sqrt{1.69} + \sqrt{0.49}) \times \sqrt{400}$$​​

Solution:.
​$$\sqrt{1.69} = 1.3\\\ \\\sqrt{0.49} = 0.7\\\ \\\sqrt{400} = 20$$

Then the value of $$(\sqrt{1.69} + \sqrt{0.49}) \times \sqrt{400}$$

=  (1.3 + 0.7)$$\times20$$

= 2$$\times20$$​​

                           = 40