Shanti Sweets Stall was placing an order for making cardboard boxes for packing their sweets. Two sizes of boxes were required. The bigger of dimensions 25 cm × 20 cm × 5 cm and the smaller of dimensions 15 cm × 12 cm × 5 cm. For all the overlaps, 5% of the total surface area is required extra. If the cost of the cardboard is rs4 for 1000 cm2 , find the cost of cardboard required for supplying 250 boxes of each kind.
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) cm2
= 2(500 + 100 + 125) cm2
= 1450 cm2
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) cm2
= 2(180 + 60 + 75) cm2
= 630 cm2
Total surface area of 250 boxes of each type = 250(1450 + 630)cm2
= 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 = rs (546000 × 4)/1000 = rs 2184
