(for examination) a sweet stall was placing order for making cardboard boxes for packing their sweets. two sizes of boxes were required. the bigger dimensions 15cmx12cmx5cm. for all the overlaps, 5% of the total surface area is required extra. if the cost of the cardboard is rs.4 for 1000cm(square), find the cost of cardboard required for supplying 250 boxes of each kind.

Rs 2,184

Explanation:

1) The statement is incomplete. The complete statement contains the information of the dimensions of both bigger and smaller cardboard boxes.

2) The dimesions of bigger cardboard boxes are 25cm * 20 cm * 5 cm

3) The dimensions of smaller cardboard boxes are 15 cm * 12 cm * 5cm

4) For bigger cardboard boxes:

length, l = 25 cm
width, w = 20 cm
height, h = 5 cm

surface of each bigger carboard box = 2 [ l*w + l*h + w*h] = 2 [25*20 + 25*5 + 20*5] cm^2 = 1450 cm^2

total surface of 250 bigger cardboard boxes = 250 * 1450 cm^2 = 3625,500 cm^2

5% of the total surface area extra = 362,500cm^2 * 5 / 100 = 18,125 cm^2

Total area for bigger cardboard boxes= 362,500 cm^2 +  18,125 cm^2 = 380,625 cm^2

5) Smaller cardboard boxes

length, l = 15 cm
width, w = 12 cm
height, h =  5 cm

surface of each smaller cardboard box = 2 [l*w + l*h + w*h] = 2 [ 15*12 + 15 * 5 + 12 * 5] cm^2 = 630 cm^2

total surface of 250 smaller cardboard boxes = 250 * 630 cm^2 = 157,500 cm^2

5 % extra = 157,500 cm^2 * 5 / 100 = 7,875 cm^2

total area for smaller cardboard boxes = 157,500 cm^2 + 7,875 cm^2 = 165,375 cm^2

6) total area of cardboard required  = 380,625 cm^2 + 165,375 cm^2 = 546,000 cm^2

7) Cost of cardboard required

unit cost per area * total area = (Rs 4 / 1000cm^2) * 546,000 cm^2 = Rs 2,184.

Rs 2,184