Question

Tìm các phân số tự nhiên x,y biết:

a.x/4 <3/4       b.1/5<y/5<1           c4/x=y/21=2/7

Answer 1

`x<3`

`->x= 1;2`

`----`

`1/5 < y/5<1`

`->1/5 < y/5<5/5`

`->y=2;3;4`

`-----`

`4/x=y/21=2/7`

\(\rightarrow\left\{{}\begin{matrix}\dfrac{4}{x}=\dfrac{y}{21}\\\dfrac{y}{21}=\dfrac{2}{7}\end{matrix}\right.\rightarrow\left\{{}\begin{matrix}\dfrac{4}{14}=\dfrac{6}{21}\\\dfrac{6}{21}=\dfrac{2}{7}\end{matrix}\right.\)