Question

Bài 1: Tính

a) 1/5 - 1/5 x 1/5

b) 7/18 + 6/5 : 5/2

c) 9/12 x 8/7 : 3/22

d) 25/23 : 16/9 x 46/75

Answer 1

a) \(\dfrac{1}{5}-\dfrac{1}{5}\times\dfrac{1}{5}=0\times\dfrac{1}{5}=0\)

b) \(\dfrac{7}{18}+\dfrac{6}{5}:\dfrac{5}{2}=\dfrac{7}{18}+\dfrac{6}{5}\times\dfrac{2}{5}=\dfrac{7}{18}+\dfrac{12}{25}=\dfrac{391}{450}\)

c) \(\dfrac{9}{12}\times\dfrac{8}{7}:\dfrac{3}{22}=\dfrac{72}{84}:\dfrac{3}{22}=\dfrac{6}{7}\times\dfrac{22}{3}=\dfrac{44}{7}\)

d) \(\dfrac{25}{23}:\dfrac{16}{9}\times\dfrac{46}{75}=\dfrac{25}{23}\times\dfrac{9}{16}\times\dfrac{46}{75}=\dfrac{400}{207}\times\dfrac{46}{75}=\dfrac{18\text{ }400}{15\text{ }525}=\dfrac{32}{27}\)