Cách 1:
\(\dfrac{3}{7}\) x \(\dfrac{16}{33}\) + \(\dfrac{16}{33}\) x \(\dfrac{4}{7}\)
= \(\dfrac{48}{231}\) + \(\dfrac{64}{231}\)
= \(\dfrac{112}{231}\)
= \(\dfrac{16}{33}\)
cách 2: \(\dfrac{3}{7}\) x \(\dfrac{16}{33}\) + \(\dfrac{16}{33}\) x \(\dfrac{4}{7}\)
= \(\dfrac{16}{33}\) x ( \(\dfrac{3}{7}\) + \(\dfrac{4}{7}\))
= \(\dfrac{16}{33}\) x \(\dfrac{7}{7}\)
= \(\dfrac{16}{33}\)