Đáp án và lời giải
Đáp án:A
Lời giải:Ta có: $35dm = 30dm + 5dm = 3m + \frac{1}{2}m = 3\frac{1}{2}m,$ 4km = 4000m, $\begin{gathered} 8m\,12cm = 8m + 12cm \ \\ \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = 80dm + 10cm + 2cm \ \\ \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = 80dm + 1dm + \frac{1}{5}dm \ \\ \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = 81\frac{1}{5}dm\, > 81\frac{1}{6}dm, \ \\ \end{gathered} $ $\begin{gathered} 135m = 100m + 35m \ \\ \,\,\,\,\,\,\,\,\,\,\,\, = 1hm + \frac{{35}}{{100}}hm \ \\ \,\,\,\,\,\,\,\,\,\,\, = 1hm + \frac{7}{{20}}hm \ \\ \,\,\,\,\,\,\,\,\,\,\, = 1\frac{7}{{20}}hm < 1\frac{2}{3}hm. \ \\ \end{gathered} $ Khẳng định đúng là: 135 m < $1\frac{2}{3}$ hm.
