Find the cost of the paper for the walls of the room if each piece of paper is 40 cm wide and 60 cm long : the room is 6 m long, 4 m wide, 3 m high and the cost of paper is Rs 1.40 per piece; allow 11 m square for doors, etc., and assume that a whole number
of pieces has to be bought.

For the second question, the number of 0.40 pieces that fit in the perimeter will be 15+15+10+10 = 50 pieces

and in the height will fit 5 pieces of 0.60 m long that will give 250 pieces minus the surface allowed for doors etc we will obtain 250 pieces minus 11/0.24(turning the allowed surface to pieces) = 45.8 pieces, I would say 48 pieces
250-48=202 pieces times 1.40 Rs. = 282.80 Rs total

The first question was already solved, I agree with the solution. And the area that remains over is 0 m

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