145; Сократите дроби: a) 6, 6, 9, 9 10' 18' 15' 24' б) 2, 3, 30, 7. 12' 15' 6'42' B) 12, 99, 5, 20 60' 22' 100' 1000

Сокращение дроби - это деление числителя и знаменателя на общий множитель.

a)

1. $$\frac{6}{10} = \frac{6:2}{10:2} = \frac{3}{5}$$.
2. $$\frac{6}{18} = \frac{6:6}{18:6} = \frac{1}{3}$$.
3. $$\frac{9}{15} = \frac{9:3}{15:3} = \frac{3}{5}$$.
4. $$\frac{9}{24} = \frac{9:3}{24:3} = \frac{3}{8}$$.

б)

1. $$\frac{2}{12} = \frac{2:2}{12:2} = \frac{1}{6}$$.
2. $$\frac{3}{15} = \frac{3:3}{15:3} = \frac{1}{5}$$.
3. $$\frac{30}{6} = \frac{30:6}{6:6} = \frac{5}{1} = 5$$.
4. $$\frac{7}{42} = \frac{7:7}{42:7} = \frac{1}{6}$$.

в)

1. $$\frac{12}{60} = \frac{12:12}{60:12} = \frac{1}{5}$$.
2. $$\frac{99}{22} = \frac{99:11}{22:11} = \frac{9}{2} = 4\frac{1}{2}$$.
3. $$\frac{5}{100} = \frac{5:5}{100:5} = \frac{1}{20}$$.
4. $$\frac{20}{1000} = \frac{20:20}{1000:20} = \frac{1}{50}$$.

Ответ: a) 3/5, 1/3, 3/5, 3/8; б) 1/6, 1/5, 5, 1/6; в) 1/5, 9/2, 1/20, 1/50