Question

Tính nhanh:

3/7:1/5+6/7:1/5-2/7:1/5

Giups ples

Answer 1

\(\dfrac{3}{7}:\dfrac{1}{5}+\dfrac{6}{7}:\dfrac{1}{5}-\dfrac{2}{7}:\dfrac{1}{5}=\dfrac{3}{7}\times5+\dfrac{6}{7}\times5-\dfrac{2}{7}\times5=5\times\left(\dfrac{3}{7}+\dfrac{6}{7}-\dfrac{2}{7}\right)=5\times\dfrac{7}{7}=5\times1=5\)

Answer 2

3/7:1/5+6/7:1/5-2/7:1/5

= \(\left(\dfrac{3}{7}+\dfrac{6}{7}-\dfrac{2}{7}\right):\dfrac{1}{5}\)

= 1 : \(\dfrac{1}{5}\)

= 5

Answer 3

= 1/5 . ( 3/7 + 6/7 - 2/7)

= 1/5 . 1

= 1/5

Answer 4

\(\dfrac{3}{7}:\dfrac{1}{5}+\dfrac{6}{7}:\dfrac{1}{5}-\dfrac{2}{7}:\dfrac{1}{5}\)

=\(\left(\dfrac{3}{7}+\dfrac{6}{7}-\dfrac{2}{7}\right):\dfrac{1}{5}\)

=1:\(\dfrac{1}{5}\)

=1x\(\dfrac{1}{5}\)

=\(\dfrac{1}{5}\)