Đáp án:
$\\$
$\dfrac{ 12,75 × \dfrac{4}{25} × 1,8}{1 \dfrac{1}{2} × 2,04 ÷ 20}$
$= \dfrac{ \dfrac{51}{4} × \dfrac{4}{25} × \dfrac{9}{5} }{ \dfrac{3}{2} × \dfrac{51}{21} × \dfrac{1}{20} }$
$= \dfrac{ \dfrac{51}{25} × \dfrac{4}{4} × \dfrac{9}{5} }{ \dfrac{3}{2} × \dfrac{51}{21} × \dfrac{1}{20} }$
$= \dfrac{1 × \dfrac{9}{5} }{ \dfrac{3}{2} × \dfrac{1}{20} }$
$= \dfrac{ \dfrac{9}{5} }{\dfrac{3}{40} }$
`= 9/5 ÷ 3/40`
`=9/5 × 40/3`
`= 24`