Question

Bài 10: Tính

a) \(\frac{5}{9}:\frac{-5}{3}\)                               b) \(\frac{2}{7}:\frac{3}{4}\)                            c) \(\frac{-3}{7}:9\)

Answer 1

a ) \(\frac{5}{9}:\frac{-5}{3}=\frac{5}{9}.\frac{3}{-5}=\frac{1.1}{3.-1}=\frac{1}{-3}=-\frac{1}{3}\)

b ) \(\frac{2}{7}:\frac{3}{4}=\frac{2}{7}.\frac{4}{3}=\frac{8}{21}\)

c ) \(\frac{-3}{7}:9=\frac{-3}{7}.\frac{1}{9}=\frac{-1.1}{7.3}=\frac{-1}{21}=-\frac{1}{21}\)

Answer 2

a) \(\frac{5}{9}:\frac{-5}{3}\)
\(\Rightarrow\frac{5}{9}.-\frac{3}{5}=-\frac{15}{45}=-\frac{1}{3}\)
b) \(\frac{2}{7}:\frac{3}{4}\)
\(\Rightarrow\frac{2}{7}.\frac{4}{3}=\frac{8}{21}\)
c) \(\frac{-3}{7}:9\)
\(\Rightarrow\frac{-3}{7}.\frac{1}{9}=\frac{-3}{63}=\frac{-1}{21}\)
Chúc bạn học tốt ^^