Răspuns :
1 m = 10 dm
1 dam = 100 dm
1 hm = 1000 dm
1 km .......... 10000 dm
2,31 km .......... x dm
[tex]\Rightarrow \text{x} = \dfrac{2,31\cdot 10000}{1} \Rightarrow \text{x} = 23100[/tex]
=> 2,31km = 23100 dm
1 dam = 100 dm
1 hm = 1000 dm
1 km .......... 10000 dm
2,31 km .......... x dm
[tex]\Rightarrow \text{x} = \dfrac{2,31\cdot 10000}{1} \Rightarrow \text{x} = 23100[/tex]
=> 2,31km = 23100 dm