Question

Đề: Tính bằng cách thuận tiện nhất

Answer 1

b) \(\dfrac{7}{5}\times\dfrac{1}{2}-\dfrac{3}{5}\times\dfrac{1}{2}=\left(\dfrac{7}{5}-\dfrac{3}{5}\right)\times\dfrac{1}{2}=\dfrac{4}{5}\times\dfrac{1}{2}=\dfrac{4}{10}=\dfrac{2}{5}\)

Answer 2

= 2/5 

Answer 3

7/5 x 1/2 - 3/5 x 1/2

=1/2 x ( 7/5 - 3/5 ) 

=1/2 x 4/5 = 1x4 ; 2x5 

= 4/10 = 2/5  nha