Question

The length breadth and height of a room is 5 metre 4 metre and the cost of whitewashing its four walls @ rupees 7.50 per metre square

Answer 1

Answer:

Area of 4 walls= 2h (l+b)

= 2×3(5+4)

=54 sq. meter

Area of celling = (l×b)

= 5×4 = 20sq. meter

area of whitewashing =54+20 = 74 sq.m

cost of whitewashing =7.50×74 = Rs.555

Answer 2

Step-by-step explanation:

Length (l) of room = 5m

Breadth (b) of room = 4m

Height (h) of room = 3m

It can be observed that four walls and the ceiling of the room are to be white washed.

Total area to be white washed = Area of walls + Area of ceiling of room

= 2lh+2bh+lb

= [2×5×3+2×4×3+5×4]

= (30+24+20)

= 74

Area = 74 m2

Also,

Cost of white wash per m2 area = Rs.7.50 (Given)

Cost of white washing 74 m2 area = Rs. (74×7.50)

= Rs. 555