Question

the length breadth and height of a room are 5m 4m 3m respectively.find the cost of white washing the inner of the room and ceiling at the rate of rs.50 per square metre.

Answer 1

c.s area of room =2h(l+b)
= 2×3(5+4)
= 6×9=54 cm2
total cost = 54×50=2700

Answer 2

Total surface area to be painted = 2(lb/2+bh+lh)

= 2 ( 5*4/2 + 4*3 + 3*5 )

= 2 (20/2 + 12 + 15)

= 2( 37 )

= 74sq mt

Total cost = 74*50 = 3700 /-

check answer

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