Найдите значение выраженияа) 8/19 + 10/19 - 11/19 б) 10 4/21 - ( 4 10/21 + 3 19/21)

а)
1) [tex] \frac{8}{19}+ \frac{10}{19}= \frac{18}{19} " alt=" \frac{8}{19}+ \frac{10}{19}- \frac{11}{19} 1) [tex] \frac{8}{19}+ \frac{10}{19}= \frac{18}{19} " align="absmiddle" class="latex-formula">
2) $\frac{18}{19}- \frac{11}{19} = \frac{7}{19}$
Ответ: $\frac{7}{19}$
б) 10 4/21 - ( 4 10/21 + 3 19/21)
1) $4 \frac{10}{21}+3 \frac{19}{21} =7 \frac{29}{21}=8 \frac{8}{21}$
2) $10 \frac{4}{21}- 8 \frac{8}{21} =9 \frac{14}{24}-8 \frac{8}{21} =1 \frac{6}{21}= 1 \frac{2}{7}$
Ответ: $1 \frac{2}{7}$