4/7 * 5/11 + 4/7 * 6/11+ (-2/3) = 4/7 * (5/11 + 6/11) + (-2/3)
= 4/7 *1 + (-2/3)
= 4/7 + (-2/3)
= -2/21
\(\frac{4}{7}.\frac{5}{11}+\frac{4}{7}.\frac{6}{11}+\frac{-2}{3}\)
=\(\frac{4}{7}.\left(\frac{5+6}{11}\right)+\frac{-2}{3}\)
=\(\frac{4}{7}.1+\frac{-2}{3}\)
=\(\frac{4}{7}+\frac{-2}{3}\)
=\(\frac{-2}{21}\)
CHÚC BẠN HỌC TỐT