The length of a rectangular hall is twice of its breadth. If the area of the hall is 338 sq. metre, then its perimeter is

Correct option is B

Given:

The length (L) of a rectangular hall is twice its breadth (B).

Area of the hall = 338 m².

Find the perimeter.

Concept Used:
Area and perimeter 

Formula Used:

Area of a rectangle = L ×  B

Perimeter of a rectangle = 2(L + B)

Solution:

Given ; L = 2B

Area:

​$$L \times B = 338 \\ \ \\2B \times B = 338\\ \ \\2B^2 = 338\\ \ \\B^2 = 169$$​​

B = 13 m

Then,

L = 2 × 13 = 26 m

Perimeter = 2(26 + 13) = 2 × 39 = 78 m