Question

34. A sweet seller was placing an order for making cardboard boxes for packing the sweets. Two
different shapes of boxes were required. One box of dimension 25 cm x 20 cm x 5 cm and the other box
of height 23 cm and radius 7 cm. If the cost of the card board is Rs 8 for 1000 cm-, find the cost of
cardboard required for supplying 100 cuboidal and 200 oylindrical boxes.

Answer 1

Dimension of bigger box = 25 cm × 20 cm × 5 cm

Total surface area of bigger box = 2(lb + bh + lh)

  = 2(25×20 + 20×5 + 25×5)

 = 1450cm2

Dimension of smaller box = 15 cm × 12 cm × 5 cm

Total surface area of smaller box = 2(lb + bh + lh)

= 2(15×12 + 12×5 + 15×5)

= 630cm2

Total surface area of 250 boxes of each type = 250(1450 + 630)                                             =250×2080 cm2 = 520000 cm2

Extra area required = 5/100(1450 + 630) × 250 cm2 = 26000 cm2

Total Cardboard required = 520000 + 26000 cm2 = 546000 cm2

Total cost of cardboard sheet = ₹(546000 × 4)/1000 = ₹ 2184