6 7.23--15- 19 19 16

7. $$23\frac{6}{19}-15\frac{16}{19} = (23-15) + (\frac{6}{19} - \frac{16}{19}) = 8 - \frac{10}{19} = 7 + 1 - \frac{10}{19} = 7 + \frac{19}{19} - \frac{10}{19} = 7\frac{9}{19}$$.

Ответ: $$7\frac{9}{19}$$