28.
The cost of carpeting a room 18m long with a carpet 75cm wide at 45 paise per meter
is Rs 81. The breadth of the room is
(a) 7m
(b) 7.5m
(C) 8m
(d) 8.5
Answers
Correct question:-
The cost of carpeting a room 18m long with a carpet 75 cm wide at Rs. 45 per meter is Rs 810. The breadth of the room is:
(a) 7 m
(b) 7.5 m
(C) 8 m
(d) 8.5 m
Answer:-
The breadth of the room is 7.5 m.
Explanation:-
Given :
Length of room = 18 m
Width of the carpet => 75 cm = 0.75 m
Cost of carpeting at the rate of Rs. 45 per meter = Rs. 810
Therefore, Length of the carpet = Total cost / Rate of carpeting per metre
Now, we know the length of the room.
And the carpet is covering the whole room, So:-
Area of carpet = Area of room
Now, We will find the area of the carpet. As it is a rectangular room, the carpet is also in the same shape. As we know, the formula of the area of rectangle is = (Length × Breadth) sq. unit
Hence, the area of the carpet or the room is 135 m.
Therefore, Breadth of room = Area of the room/ Length of the room
Hence, The breadth of the room is 7.5 m.