(-3/7 + 1/4) : 15/28 = -3/7 + 1/4 : 15/28 = -3/7 + (1/4 : 15/28) =-3/7 + 7/15 =4/105 HỌC TỐT NHÉ ^_^
\(\left(-\frac{3}{7}+\frac{1}{4}\right):\frac{15}{28}\)
=\(\left(\frac{-12}{28}+\frac{7}{28}\right):\frac{15}{28}\)
=\(\frac{-5}{28}:\frac{15}{28}\)
=\(\frac{-5}{28}.\frac{28}{15}\)
=\(-\frac{1}{3}\)
\(\left(-\frac{3}{7}+\frac{1}{4}\right):\frac{15}{28}\)
\(=\left(-\frac{12}{28}+\frac{7}{28}\right):\frac{15}{28}\)
\(=\left(-\frac{5}{28}\right):\frac{15}{28}\)
\(=\left(-\frac{5}{28}\right).\frac{28}{15}\)
\(=-\frac{5}{15}=-\frac{1}{3}\)
