Không quy đồng tử số và mẫu số hãy so sánh các p/s sau :
\(\displaystyle \frac{{12}}{{14}}
\) ; \(\displaystyle \frac{{1212}}{{1414}}
\) ; \(\displaystyle \frac{{121212}}{{141414}}
\)
\(\displaystyle \frac{{24}}{{35}} \) ; \(\displaystyle \frac{{2424}}{{3535}} \) ; \(\displaystyle \frac{{242424}}{{353535}} \)
\(\displaystyle \frac{{ab}}{{cd}} \) ; \(\displaystyle \frac{{abab}}{{cdcd}} \) ; \(\displaystyle \frac{{ababab}}{{cdcdcd}} \)