Question

Найдите значение суммы:1)-2+1 7/8; 2)-1+2 1/9; 3) -4 +3 1/2; 4)-5/7+4/7; 5)-5/8+7/8; 6)-1/6 +1;

Answer 1

$1)-2+1frac{7}{8}=-(2-1frac{7}{8})=-(1frac{8}{8}-1frac{7}{8})=-frac{8-7}{8}= -fra{1}{8}\ \2)-1+2frac{1}{9}=2frac{1}{9}-1=(2-1)frac{1}{9} =1frac{1}{9}\\3) -4 +3frac{1}{2}=-(4-3frac{1}{2})=-(3frac{2}{2}-3frac{1}{2})=-frac{1}{2}\\4)-frac{5}{7}+frac{4}{7}=-(frac{5}{7} -frac{4}{7})=-frac{5-4}{7}=-frac{1}{7}\\5)-frac{5}{8}+frac{7}{8}=frac{7}{8}-frac{5}{8}=frac{7-5}{8}=frac{2}{8}\\6)-frac{1}{6}+1=1-frac{1}{6}=frac{6}{6}-frac{1}{6}=frac{6-1}{6}=frac{5}{6}$