1/2+2/5,1/2-2/5,1/4+1/6,9/10-5/6Только распишите пожалуйста.

1/2+2/5= 5/10+ 4/10= 9/10; 1/2-2/5= 5/10-4/10= 1/10; 1/4+1/6= 3/12+ 2/12= 5/12; 9/10- 5/6= 27/30- 25/30= 2/30= 1/15.

[latex] \frac{1}{2} + \frac{2}{5}= \frac{5+4}{10} = \frac{9}{10} [/latex] [latex] \frac{1}{2} - \frac{2}{5} = \frac{5-4}{10} = \frac{1}{10} [/latex] [latex] \frac{1}{4}+ \frac{1}{6}= \frac{6+4}{24} = \frac{10}{24}= \frac{5}{12} [/latex] [latex] \frac{9}{10} - \frac{5}{6}= \frac{27-25}{30} = \frac{2}{30}= \frac{1}{15} [/latex]