Номер 821 )))))))))))))))))))

1)
$\frac{3}{10} + \frac{9}{10} = \frac{3+9}{10} = \frac{12}{10} =1,2$
2)
$1 \frac{5}{10} +2 \frac{3}{10} = \frac{15}{10} + \frac{23}{10} = \frac{15+23}{10} = \frac{38}{10} =3,8$
3)
$\frac{23}{100} + \frac{19}{100} = \frac{23+19}{100} = \frac{42}{100} =0,42$
4)
$8 \frac{91}{1000} + \frac{985}{1000} = \frac{8091}{1000} +\frac{985}{1000}= \frac{8091+985}{1000} = \frac{9076}{1000} =9,076$
5)
$2 \frac{11}{100} + \frac{95}{100} = \frac{211}{100} +\frac{95}{100} = \frac{211+95}{100} = \frac{306}{100} =3,06$
6)
$\frac{813}{1000} +1 \frac{7}{1000} = \frac{813}{1000}+ \frac{1007}{1000} = \frac{813+1007}{1000} = \frac{1820}{1000} =1,82$