Đáp án:
$\dfrac{205}{474}$
Giải thích các bước giải:
$A=\dfrac{\dfrac{2}{3}+\dfrac{2}{9}+\dfrac{1}{4}}{\dfrac{4}{3}+\dfrac{4}{5}+\dfrac{2}{4}}$
$A=\dfrac{\dfrac{24}{36}+\dfrac{8}{36}+\dfrac{9}{36}}{\dfrac{80}{60}+\dfrac{48}{60}+\dfrac{30}{60}}$
$A=\dfrac{\dfrac{24+8+9}{36}}{\dfrac{80+48+30}{60}}$
$A=\dfrac{\dfrac{41}{36}}{\dfrac{158}{60}}$
$A=\dfrac{41}{36}:\dfrac{158}{60}$
$A=\dfrac{41}{36}\cdot\dfrac{60}{158}$
$A=\dfrac{205}{474}$
