A classroom is $12 m$ long. $7 m$ wide and $4 m$ high. Find the cost of repairing the walls and ceiling the rate of Rs. $15$ per square metre.

Open in App

Solution

Given length of classroom = 12 cm
width of classroom = 7 m
height of classroom =4 m
Area of 4 walls = 2(l+b)h
area of ceiling = lb
Total area = 2(l+b)h+lb
$= 2 [12 + 7] \times 4 + 12 \times 7$
$= 2 \times 19 \times 4 + 84$
$= 152 + 84$
Total area = $236 m^{2}$
Cost of repairing
$= 236 \times 15$ Rs
Total cost = 3540 Rs

Suggest Corrections

Similar questions

A swimming pool is 20 m long, 15 m wide and 3 m deep. Find the cost of repairing the floor and wall at the rate of Rs 25 per square metre.

The cost of preparing the walls of a room 12 m long at the rate of Rs 1.35 per square metre is Rs 340.20 and the cost of matting the floor at 85 poise per square metre is Rs 91.80. Find the height of the room.

Q. A godown is 50 m long, 40 m broad and 10 m high. Find the cost of whitewashing its four walls and ceiling at Rs 20 per square metre.

Q. The cost of papering the four walls of a room

12 m

long at Rs.

6.50

per square metre is Rs.

1638

and the cost of matting the floor at Rs.

3.50

per square metre is Rs.

378

. Find the height of the room.

Q. A classroom is

7 m

long,

6 m

broad and

4 m

high. The doors and windows occupy an area of

7 m^{2}

. Find the cost of whitewashing the walls and roof at the rate of

R s . 15 p e r m^{2}

Join BYJU'S Learning Program

A classroom is 12 m long. 7 m wide and 4 m high. Find the cost of repairing the walls and ceiling the rate of Rs.15 per square metre.

Given length of classroom = 12 cmwidth of classroom = 7 mheight of classroom =4 mArea of 4 walls = 2(l+b)harea of ceiling = lbTotal area = 2(l+b)h+lb=2[12+7]×4+12×7=2×19×4+84=152+84Total area = 236m2Cost of repairing=236×15 RsTotal cost = 3540 Rs

A classroom is $12 m$ long. $7 m$ wide and $4 m$ high. Find the cost of repairing the walls and ceiling the rate of Rs. $15$ per square metre.