Question

(3,8-x)+1/5=3 1/7
Сколько будет

Answer 1

$\displaystyle (3,8-x)+\frac{1}{5}=3\frac{1}{7}\\\\ 3,8-x+\frac{1}{5}=\frac{22}{7}\\\\ \frac{19}{5}-x+\frac{1}{5}=\frac{22}{7}\\\\ 4-x=\frac{22}{7}\\\\ -x=\frac{22}{7}-4\\\\ -x=-\frac{6}{7}\\\\ x=\frac{6}{7}$