7 б) $$17\frac{1}{24}-5\frac{5}{24}= 16\frac{25}{24}-5\frac{5}{24}= 11 \frac{20}{24}= 11\frac{5}{6}$$
8 б) $$4\frac{3}{4} - 1\frac{1}{3} = 4\frac{9}{12}-1\frac{4}{12}= 3 \frac{5}{12}$$
9 б) $$7\frac{4}{12}-2\frac{3}{3}= 7\frac{1}{3}-3= 4\frac{1}{3}$$
10 б) $$4\frac{3}{15}-1\frac{4}{20}= 4\frac{1}{5}-1\frac{1}{5}=3$$