a) 3 x (1/7 + 1/3 - 3/4) : 11/14
= 3 x (10/21 - 3/4) : 11/14
= 3 x (-23/84) : 11/14
= (-23/28) : 11/14
= (-23/28) x 14/11
= -23/22
Vậy 3 x (1/7 + 1/3 - 3/4) : 11/14 = -23/22.
b) 2$\frac{2}{17}$ x 1$\frac{1}{24}$ x 5$\frac{2}{5}$ x 3$\frac{7}{9}$ x 2
= 36/17 x 25/24 x 27/5 x 34/9 x 2
= 75/34 x 27/5 x 34/9 x 2
= 405/34 x 34/9 x 2
= 45 x 2
= 90
Vậy 2$\frac{2}{17}$ x 1$\frac{1}{24}$ x 5$\frac{2}{5}$ x 3$\frac{7}{9}$ x 2 = 90
c) (1$\frac{3}{5}$ + 2$\frac{1}{5}$) x 1$\frac{1}{10}$ + (1$\frac{7}{10}$ - 4/5) : 3/7
= (8/5 + 11/5) x 11/10 + (17/10 - 4/5) x 7/3
= 19/5 x 11/10 + 9/10 x 7/3
= 209/50 + 21/10
= 157/25
Vậy (1$\frac{3}{5}$ + 2$\frac{1}{5}$) x 1$\frac{1}{10}$ + (1$\frac{7}{10}$ - 4/5) : 3/7 = 157/25
