a. 3 3/4 + 1 3 / 8 – 2/3 b. 3/7 x 4/5 + 5/7 c.3/12 : 2/3 + 1 1/8

Bạn tham khảo :

a . 

$3 \dfrac{3}{4} + 1 \dfrac{3}{8} – \dfrac{2}{3}$

$=\dfrac{15}{4} + \dfrac{11}{8} – \dfrac{2}{3}$

$= \dfrac{41}{8} – \dfrac{2}{3}$
$=\dfrac{107}{24}$

b . 

$\dfrac{3}{7} × \dfrac{4}{5} + \dfrac{5}{7}$

$= \dfrac{12}{35} + \dfrac{5}{7}$

$=\dfrac{37}{35}$

c. 

$\dfrac{3}{12} : \dfrac{2}{3} + 1 \dfrac{1}{8}$

$= \dfrac{3}{8} + \dfrac{9}{8}$

$= \dfrac{3}{2}$