To determine the cost of wood required for 250 boxes of each type, we need to calculate the total surface area of both types of boxes, including the extra 5% for overlaps.
1. Surface Area Calculation:
- Larger Box:
Dimensions: 25 cm x 20 cm x 5 cm
Surface Area = 2(lw + lh + wh)
\[ = 2(25 \times 20 + 25 \times 5 + 20 \times 5) \]
\[ = 2(500 + 125 + 100) \]
\[ = 2 \times 725 \]
\[ = 1450 \text{ cm}^2 \]
Including 5% extra:
\[ = 1450 \times 1.05 = 1522.5 \text{ cm}^2 \]
- Smaller Box:
Dimensions: 15 cm x 12 cm x 5 cm
Surface Area = 2(lw + lh + wh)
\[ = 2(15 \times 12 + 15 \times 5 + 12 \times 5) \]
\[ = 2(180 + 75 + 60) \]
\[ = 2 \times 315 \]
\[ = 630 \text{ cm}^2 \]
Including 5% extra:
\[ = 630 \times 1.05 = 661.5 \text{ cm}^2 \]
2. Total Surface Area for 250 Boxes of Each Type:
- Total for larger boxes:
\[ = 250 \times 1522.5 = 380625 \text{ cm}^2 \]
- Total for smaller boxes:
\[ = 250 \times 661.5 = 165375 \text{ cm}^2 \]
- Total Surface Area:
\[ = 380625 + 165375 = 546000 \text{ cm}^2 \]
3. Cost Calculation:
Cost of wood = Total Surface Area \(\times\) Cost per cm\(^2\)
\[ = 546000 \times 4 = 2184000 \text{ Rs} \]
Thus, the cost of the wood required for supplying 250 boxes of each type is Rs. 2184000.