Jeżeli 1 dm = 10 cm to: 1 cm =\frac{1}{10}dm
1dm^2=10 cm x 10 cm = 100$cm^2$-------------1cm^2=\frac{1}{100}dm^2=0,01dm^2
1dm^3=10cm x 10cm x 10cm = 1000$cm^3$----------1cm^3=\frac{1}{1000}dm^3=0,001dm^3
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1m = 100cm
1m^2=100cm x 100cm = 10 000$cm^2$ -----12cm^2=12 \cdot\frac{1}{10000}m^2=0,0012m^2
1m^2=10dm x 10dm = 100$dm^2$
1m^3= 10dm x 10dm x 10dm = 1000$dm^3$=1000 l [litrów] gdyż 1dm^3=1l
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1km 1000 m 1m=\frac{1}{1000}km
1 km = 1000m/10 = 100dm (bo 1m = 10dm)
Jak czegoś nie rozumiesz pisz na skrzynkę.