# The length, breadth and height of a room are in ratio 3:2:1. If breadth and height are halved while the length is doubled, then the total area of the four walls of the room will

A. remain the same

B. decrease by 13.64%

C. decrease by 15%

D. decrease by 18.75%

E. decrease by 30%

**Answer: Option E **

__Solution(By Examveda Team)__

Let length, breadth and height of the room be 3, 2, 1 unit respectively. Area of walls = 2(l + b) × h = 2(3 + 2) × 1 = 10 sq. unit.

Now, length, breadth and height of room will become 6, 1 and $$\frac{1}{2}$$ respectively.

Now, area of walls = $$2\left( {6 + 1} \right) \times \frac{1}{2}$$ = 7 sq. unit.

% decrease in the area of walls = $$\left( {10 - 7} \right) \times \frac{{100}}{{10}}$$ = 30%

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Related Questions on Percentage

A. $$\frac{1}{4}$$

B. $$\frac{1}{3}$$

C. $$\frac{1}{2}$$

D. $$\frac{2}{3}$$

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