Để điền dấu thích hợp vào các chỗ chấm, ta cần quy đổi đơn vị để so sánh các số liệu.

1. **850 cm² ……… 12 dm²**
- \(12 \, \text{dm}^2 = 12 \times 100 \, \text{cm}^2 = 1200 \, \text{cm}^2\)
- **Đáp án:** 850 cm² < 12 dm²

2. **302 mm² ……… 3 dm²**
- \(3 \, \text{dm}^2 = 3 \times 10000 \, \text{mm}^2 = 30000 \, \text{mm}^2\)
- **Đáp án:** 302 mm² < 3 dm²

3. **2 mm² ……… 3 m²**
- \(3 \, \text{m}^2 = 3 \times 1000000 \, \text{mm}^2 = 3000000 \, \text{mm}^2\)
- **Đáp án:** 2 mm² < 3 m²

4. **92 dm² ……… 4 m²**
- \(4 \, \text{m}^2 = 4 \times 10000 \, \text{dm}^2 = 40000 \, \text{dm}^2\)
- **Đáp án:** 92 dm² < 4 m²

5. **51 km² ………… 510 hm²**
- \(51 \, \text{km}^2 = 51 \times 100 \, \text{hm}^2 = 5100 \, \text{hm}^2\)
- **Đáp án:** 51 km² > 510 hm²

6. **2015 m² ……… 2 hm²**
- \(2 \, \text{hm}^2 = 2 \times 10000 \, \text{m}^2 = 20000 \, \text{m}^2\)
- **Đáp án:** 2015 m² < 2 hm²

7. **15 m² ……… 32 km²**
- \(32 \, \text{km}^2 = 32 \times 1000000 \, \text{m}^2 = 32000000 \, \text{m}^2\)
- **Đáp án:** 15 m² < 32 km²

8. **45 m² ……. 3200 hm²**
- \(3200 \, \text{hm}^2 = 3200 \times 10000 \, \text{m}^2 = 32000000 \, \text{m}^2\)
- **Đáp án:** 45 m² < 3200 hm²

9. **67 m² ………. 6700 cm²**
- \(6700 \, \text{cm}^2 = 67 \times 100 \, \text{cm}^2 = 6700 \, \text{cm}^2\)
- **Đáp án:** 67 m² > 6700 cm²

10. **27 dm² 34 cm² …….. 2734 cm²**
- \(27 \, \text{dm}^2 = 27 \times 100 \, \text{cm}^2 = 2700 \, \text{cm}^2\)
- \(2700 \, \text{cm}^2 + 34 \, \text{cm}^2 = 2734 \, \text{cm}^2\)
- **Đáp án:** 27 dm² 34 cm² = 2734 cm²

11. **573 hm² …….. 57 km²**
- \(57 \, \text{km}^2 = 57 \times 100 \, \text{hm}^2 = 5700 \, \text{hm}^2\)
- **Đáp án:** 573 hm² < 57 km²

12. **34 dm² 34 mm² ……… 3434 cm²**
- \(34 \, \text{dm}^2 = 34 \times 100 \, \text{cm}^2 = 3400 \, \text{cm}^2\)
- \(34 \, \text{mm}^2 = 0.34 \, \text{cm}^2\)
- \(3400 \, \text{cm}^2 + 0.34 \, \text{cm}^2 = 3400.34 \, \text{cm}^2\)
- **Đáp án:** 34 dm² 34 mm² < 3434 cm²

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