Question

вычислите: (4 6/7:(5/6+8/21)-2 5/13)*8 2/3

Answer 1

Решаем каждый пример:
1)$frac{5}{6}+ frac{8}{21}= frac{5*21}{6*21}+ frac{8*6}{21*6}= frac{105}{126}+ frac{48}{126}= frac{153}{126}= frac{17}{14}$

2)$4 frac{6}{7} : frac{17}{14}= frac{4*7+6}{7} : frac{17}{14}= frac{34}{7}: frac{17}{14}= frac{34}{7}* frac{14}{17}= frac{34*14}{7*17}= frac{4}{1}=4$

3)$4- 2frac{5}{13}= frac{4}{1}- frac{2*13+5}{13}= frac{4}{1}- frac{31}{13}= frac{4*13}{1*13}- frac{31*1}{13*1}= frac{52}{13}- frac{31}{13}= frac{21}{13}$

4) $frac{21}{13}*8 frac{2}{3}= frac{21}{13}* frac{8*3+2}{3}= frac{21}{13} * frac{26}{3}= frac{21*26}{13*3}= frac{14}{1}=14$