Giải bài 2 trang 45 - SGK Toán lớp 5

Mẫu: $\bf 315cm = 3,15m$

$\bf \text{Cách làm}: \\ 315cm = 300cm + 15cm = 3m \, 15cm \\ \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,= 3\dfrac{15}{100}m = 3,15m.$

Ta có:

$\begin{align} 234cm &= 200cm + 34cm = 2m \, 34cm \\ &= 2\dfrac{34}{100}m = 2,34m \end{align}$

$\begin{align} 506cm &= 500cm + 6cm = 5m \,6cm \\ &= 5\dfrac{6}{100}m = 5,06m \end{align}$

$\begin{align} 34dm &= 30dm + 4dm = 3m \, 4dm \\ &= 3\dfrac{4}{10}m = 3,4m \end{align}$