Question

Length, breadth and height of a room are 15 metre 12m and 8 metre respectively. find the cost of whitewashing the room at the rate of Rs 8 per metre square if it has door measuring 4m ×1.5m and two Windows each measuring 3 metre×2.5 metre​

Answer 1

Answer:

total area of room is 2(l+b)×h

=15×12×8

=1440 sqare m

area of the door = l×b

=4×1.5

=6square m

area of the windows = 2 (l×b)

2(3×2.5)

2×7.5

= 15 square m

area need to be white wash =total area - area of windows and door

=1440-(6+15)

1440-21

1419 square m

rate of wash=8ruppes

cost of whitewash 8×1419=11352 ruppes

Answer 2

Step-by-step explanation:

total area of room is 2( l+b)×h

= 15×12×8

=1440 sq m

Area of the door= l× b

=4×1.5m

= 6 sq m

Area of window = 2(l × b)

= 2( 3 × 2.5)

= 15 sq m

Area need to be white wash= total area-area of window and door

= 1440-(6+15) sq m

= 1440-21

1419 sq m

Rate of wash= 8 rupees

Cost of white wash= 8 × 1419

= 11352 rupees