Điền số thích hợp vào ô trống :
a) \(\dfrac{1}{2} = \dfrac{{...}}{{12}}\)
b) \(\dfrac{7}{4} = \dfrac{{28}}{{...}}\)
c) \(\dfrac{{...}}{9} = \dfrac{{ - 20}}{{36}}\)
d) \(\dfrac{{ - 28}}{{56}} = \dfrac{4}{{...}}\)
e) \(\dfrac{{ - 16}}{{ - 36}} = \dfrac{{...}}{9}\)
f) \(\dfrac{{...}}{9} = \dfrac{4}{{...}}.\)
\(a)\,\,\,\dfrac{1}{2} = \dfrac{6}{{12}}\) vì \(1.12 = 6.2\)
\(b)\,\,\,\dfrac{7}{4} = \dfrac{{28}}{{16}}\) vì \(7.16 = 28.4\)
\(c)\,\,\,\dfrac{{ - 5}}{9} = \dfrac{{ - 20}}{{36}}\) vì \((-5).36 = (-20).9\)
\(d)\,\,\,\dfrac{{ - 28}}{{56}} = \dfrac{4}{{ - 8}}\) vì \((-28).(-8) = 4.56\)
\(e)\,\,\,\dfrac{{ - 16}}{{ - 36}} = \dfrac{4}{9}\) vì \((-16).9 = 4.(-36)\)
\(f)\,\,\,\,\dfrac{6}{9} = \dfrac{4}{6}\) vì \(6.6 = 4.9\)