$\text{5m² 30dm² = 5,3m²}$

$\text{→ 5m² 30dm² = 5$\frac{30}{100}$m² = 5,30m² = 5,3m²}$

$\text{2m² 4dm² = 2,04m²}$

$\text{→ 2m² 4dm² = 2$\frac{4}{100}$m² = 2,04m²}$

$\text{3m² 45cm² = 3,0045m²}$

$\text{→ 3m² 45cm² = 3$\frac{45}{10000}$m² = 3,0045m²}$

$\text{4m² 7cm² = 4,0007m²}$

$\text{4m² 7cm² = 4$\frac{7}{10000}$m² = 4,0007m²}$

$\text{50dm² = 0,5m²}$

$\text{50dm² = $\frac{50}{100}$m² = 0,5m²}$

$\text{9dm² = 0,09m²}$

$\text{9dm² = $\frac{9}{100}$m² = 0,09m²}$

$\text{2123cm² = 0,2123m²}$

$\text{2123cm² = $\frac{2123}{10000}$m² = 0,2123m²}$

$\text{48cm² = 0,0048m²}$

$\text{48cm² = $\frac{48}{10000}$m² = 0,0048m²}$

_____________________________________________________________

$\text{1020m² = 0,102ha}$

$\text{1020m² = $\frac{1020}{10000}$ha = 0,1020m² = 0,102ha}$

$\text{1200m² = 0,12ha}$

$\text{1200m² = $\frac{1200}{10000}$ha = 0,1200ha = 0,12ha}$

$\text{1002m² = 0,1002ha}$

$\text{1002m² = $\frac{1002}{10000}$ha = 0,1002ha}$

$\text{102m² = 0,102ha}$

$\text{102m² = $\frac{102}{10000}$ha = 0,102ha}$

________________________________________________________________

$\text{3,0009ha ; 30009m² ; 0,30009km²}$

$\text{20ha 100m² ; 200100m² ; 0,200100m²}$

$\text{6ha 50m² ; 6,0050ha ; 0,60050km²}$

$\text{0,35ha ; 3500m² ; 0,03500km²}$

$#Roa$

Đáp án:

 1a, 5,3           b, 0,5

       2,04             0,09

       3,0045         0,2123

       4,0007         0,0048

2.1020m2=0,102ha

    1200m2=0,12ha

     1002m2=0,1002ha

    102m2=0,0102ha

3.3ha9m2=3,0009ha=30009m2=0,30009km2

   20ha100m2=20,01ha=20000100m2=0,20001km2

   Học Tốt!

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