Điền dấu thích hợp (=, <, >) vào chỗ trống :
a) \(1,53 ....... 1,8\);
b) \(- 2,37 ....... 2,41\);
c) \(\dfrac{{12}}{{ - 18}}.....\dfrac{{ - 2}}{3}\)
d) \(\dfrac{3}{5}.....\dfrac{{13}}{{20}}\)
So sánh hai số thập phân, phân số cùng mẫu.
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a) \(1,53 < 1,8\);
b) \(- 2,37 > -2,41\);
c)
\(\left. \begin{gathered}
\frac{{12}}{{ - 18}} = \frac{{12:\left( { - 6} \right)}}{{\left( { - 18} \right):\left( { - 6} \right)}} = \frac{{ - 2}}{3} \hfill \\
\frac{{ - 2}}{3} \hfill \\
\end{gathered} \right\} \)\(\,\Rightarrow \dfrac{{ - 2}}{3} = \dfrac{{ - 2}}{3}\)
Do đó: \(\dfrac{{12}}{{ - 18}}=\dfrac{{ - 2}}{3}\)
d)
\(\left. \begin{gathered}
\frac{3}{5} = \frac{{3.4}}{{5.4}} = \frac{{12}}{{20}} \hfill \\
\frac{{13}}{{20}} \hfill \\
\end{gathered} \right\} \Rightarrow \dfrac{{12}}{{20}} < \dfrac{{13}}{{20}}\)
Do đó: \(\dfrac{3}{5} < \dfrac{{13}}{{20}}\)