Đáp án + Giải thích các bước giải:
Bài 1.
$5\dfrac{1}{3}+2\dfrac{2}{5} \times 1\dfrac{1}{9}$
$=\dfrac{16}{3}+\dfrac{12}{5} \times \dfrac{10}{9}$
$=\dfrac{16}{3}+\dfrac{8}{3}$
$=8$
Bài 2.
$\dfrac{9}{4}-y \times \dfrac{5}{6}=\dfrac{1}{2}+\dfrac{2}{3}$
$\dfrac{9}{4}-y \times \dfrac{5}{6}=\dfrac{7}{6}$
$y \times \dfrac{5}{6}=\dfrac{9}{4}-\dfrac{7}{6}$
$y \times \dfrac{5}{6}=\dfrac{13}{12}$
$y= \dfrac{13}{12}:\dfrac{5}{6}$
$y= \dfrac{13}{12} \times \dfrac{6}{5}$
$y=\dfrac{13}{10}$
