5/9x13/28+13/28x4/9
=(5/9+4/9)x13/28
=1x13/28
=13/28
5/9 x 13/28 +13/28 x 4/9
= 13/28 x ( 5/9 + 4/9 )
= 13/28 x 1
= 13/28
\(\frac{5}{9}.\frac{13}{28}+\frac{13}{28}.\frac{4}{9}\)
\(=\frac{13}{28}\left(\frac{5}{9}+\frac{4}{9}\right)\)
\(=\frac{13}{28}.1\)
\(=\frac{13}{28}\)
k nha
5/9x13/28+13/28x4/9
=13/28x(5/9+4/9)
=13/28x1
=13/28
bấm đúng đi