\(\dfrac{5}{13}\) \(\times\) \(\dfrac{9}{14}\) \(\times\) \(\dfrac{28}{27}\) \(\times\) \(\dfrac{26}{35}\)
= \(\dfrac{5}{13}\) \(\times\) \(\dfrac{9}{14}\) \(\times\) \(\dfrac{14\times2}{9\times3}\) \(\times\) \(\dfrac{13\times2}{5\times7}\)
= \(\dfrac{5\times9\times14\times13}{5\times9\times14\times13}\) \(\times\) \(\dfrac{2\times2}{3\times7}\)
= 1 \(\times\) \(\dfrac{4}{21}\)
= \(\dfrac{4}{21}\)