Verified answer

а)

[tex]1 - \frac{25}{28} = \frac{28}{28} - \frac{25}{28} = \frac{3}{28} [/tex]

б)

[tex]9 - \frac{4}{21} = \frac{189}{21} - \frac{4}{21} = \frac{185}{21} = 8 \frac{17}{21} [/tex]

в)

[tex]10 - 8 \frac{1}{7} = 10 - \frac{57}{7} = \frac{70}{7} - \frac{57}{7} = \frac{13}{7 } = 1 \frac{6}{7} [/tex]

г)

[tex]11 - 1 \frac{5}{8} = 11 - \frac{13}{8} = \frac{88}{8} - \frac{13}{8} = \frac{75}{8} = 9 \frac{3}{8} [/tex]