\(\frac{11}{15}=\frac{11\times39}{15\times39}=\frac{429}{585}\)
\(\frac{33}{39}=\frac{33\times15}{39\times15}=\frac{495}{585}\)
Vậy.................
ta có: \(\frac{33}{39}=\frac{33:3}{39:3}=\frac{11}{13}\)vì \(\frac{11}{13}>\frac{11}{15}\)nên \(\frac{33}{39}>\frac{11}{15}\)
\(\frac{33}{39}=\frac{33:3}{39:3}=\frac{11}{13}\)
Ta thấy:\(\frac{11}{15}< \frac{11}{13}\)
\(\Rightarrow\frac{11}{15}< \frac{33}{39}\)
\(\frac{33}{39}=\frac{33:3}{39:3}=\frac{11}{12}\)
Mà \(\frac{11}{15}< \frac{11}{12}\)
Vậy \(\frac{11}{15}< \frac{33}{39}\)
\(\frac{11}{15}\)= \(\frac{11x39}{15x39}\)= \(\frac{429}{585}\)
\(\frac{33}{39}\)= \(\frac{33x15}{39x15}\)= \(\frac{495}{585}\)
Vì \(\frac{429}{585}\)< \(\frac{495}{585}\)nên \(\frac{11}{15}\)< \(\frac{33}{39}\)