Предмет: Алгебра, автор: alammiller

1) 1 1/3- 2 1/3+ 3 2/5
2) 1- 3/5- 2/5
3) 6/7- 1 2/9+ 1/7
4) -1 2/3+ 3 1/6- 2 1/12
5) -7+6 1/2
6) 3 2/5- 4 1/5
7) 2/9+ 1/3 -7/27 + 1 31/36
8) -1- 2/5 - 7/10

Ответы

Автор ответа: МаленькийУчитель

1) $1 frac{1}{3} -2 frac{1}{3} +3 frac{2}{5} = frac{4}{3} - frac{7}{3} + frac{17}{5} = frac{20-35+51}{15} = frac{36}{15} =2,4$
2) $1-frac{3}{5} - frac{2}{5} = frac{5-3-2}{5} = frac{0}{5} =0$
3) $frac{6}{7} -1 frac{2}{9} + frac{1}{7} = frac{6}{7} - frac{11}{9} + frac{1}{7} = frac{54-77+9}{63} = frac{-14}{63}= -0,(2)$
4) $-1 frac{2}{3} +3 frac{1}{6} -2 frac{1}{12} =- frac{5}{3} + frac{19}{6} - frac{25}{12} = frac{-20+38-25}{12} = frac{-7}{12} =-0,6$
5) $-7+6 frac{1}{2} = -7+frac{13}{2} = frac{-14+13}{2} = frac{-1}{2} =-0,5$
6) $3 frac{2}{5} -4 frac{1}{5} = frac{17}{5} - frac{21}{5} = frac{17-21}{5} = frac{-4}{5} =-0,8$
7) $frac{2}{9} + frac{1}{3} - frac{7}{27} +1 frac{31}{36} = frac{2+3}{9} - frac{7}{27} + frac{67}{36} = frac{15-7}{27} + frac{67}{36} = frac{8}{27} + frac{67}{36}= frac{288+1809}{972}$ $= frac{2097}{972} =2,16$
8) $-1- frac{2}{5} - frac{7}{10} = frac{-10-4-7}{10} = frac{-21}{10} =-2,1$