Question

The expenses of carpeting a room thrice as long as it is broad, at Rs. 7.50 per square
metre, is Rs. 1,102.50. What is the breadth of the room?
A-6m
B-7m
C-8m
D-9m​

Answer 1

A - 6m

B - 7m

C - 8m

D - 9m​

explanation : so, if we use x to be the breadth of the room, the length of the room is x × 3 which is 3x m and the area is 3x^2 (3x × x) m^2. ​since the total cost is 1 102.50 rupee and the cost per m^2 is 7.50 rupee, just take the total cost divided by the cost per m^2 (i.e. 1 102.50/7.50) which is 147 m^2. that it is the area of the room. so, this means 147m^2 is equivalent to 3x^2. we divide both sides by 3 to get x^2 = 49, so that means the final answer for x is 7 m.

hope it helps :)