Question

помогите решить 1)1 2/3+2 1/4 2)3 1/3+4 2/5 3)3/5-1/5 4)4/7-6/7 5)5/7-3/5 6) 7/9-9/10

Answer 1

1)
$1 frac{2}{3} + 2 frac{1}{4} = 1 frac{8}{12} + 2 frac{3}{12} = 3 frac{11}{12}$
2)
$3 frac{1}{3} + 4 frac{2}{5} = 3 frac{5}{15} + 4 frac{6}{15} = 7 frac{11}{15}$
3)
$frac{3}{5} - frac{1}{5} = frac{2}{5}$
4)
$frac{4}{7} - frac{6}{7} = - frac{2}{7}$
5)
$frac{5}{7} - frac{3}{5} = frac{25}{35} - frac{21}{35} = frac{4}{35}$
6)
$frac{7}{9} - frac{9}{10} = frac{70}{90} - frac{81}{90} = - frac{11}{90}$