117. Сократить данные дроби. 4) 60/144, 74/666, 83/249, 840/960, 121/143, 168/216, 840/1050, 264/312, 255/285. 205/246, 148/185. 5) 750/1125, 1000/3175, 1250/2250, 675/975, 1008/1224, 1188/1485.

Решение:

4) Сокращение дробей:

• \( \frac{60}{144} = \frac{60 \div 12}{144 \div 12} = \frac{5}{12} \)
• \( \frac{74}{666} = \frac{74 \div 2}{666 \div 2} = \frac{37}{333} \)
• \( \frac{83}{249} = \frac{83 \div 83}{249 \div 83} = \frac{1}{3} \)
• \( \frac{840}{960} = \frac{840 \div 120}{960 \div 120} = \frac{7}{8} \)
• \( \frac{121}{143} = \frac{121 \div 11}{143 \div 11} = \frac{11}{13} \)
• \( \frac{168}{216} = \frac{168 \div 24}{216 \div 24} = \frac{7}{9} \)
• \( \frac{840}{1050} = \frac{840 \div 210}{1050 \div 210} = \frac{4}{5} \)
• \( \frac{264}{312} = \frac{264 \div 24}{312 \div 24} = \frac{11}{13} \)
• \( \frac{255}{285} = \frac{255 \div 15}{285 \div 15} = \frac{17}{19} \)
• \( \frac{205}{246} = \frac{205 \div 102.5? \text{ Не сокращается.}}{\text{Проверка: 205 = 5*41, 246 = 2*3*41. }} \( \frac{205}{246} = \frac{205 \div 41}{246 \div 41} = \frac{5}{6} \)
• \( \frac{148}{185} = \frac{148 \div 37}{185 \div 37} = \frac{4}{5} \)

5) Сокращение дробей:

• \( \frac{750}{1125} = \frac{750 \div 375}{1125 \div 375} = \frac{2}{3} \)
• \( \frac{1000}{3175} = \frac{1000 \div 25}{3175 \div 25} = \frac{40}{127} \)
• \( \frac{1250}{2250} = \frac{1250 \div 250}{2250 \div 250} = \frac{5}{9} \)
• \( \frac{675}{975} = \frac{675 \div 75}{975 \div 75} = \frac{9}{13} \)
• \( \frac{1008}{1224} = \frac{1008 \div 72}{1224 \div 72} = \frac{14}{17} \)
• \( \frac{1188}{1485} = \frac{1188 \div 132}{1485 \div 132} = \frac{9}{? \text{ 1485 / 132 = 11.25. }} \( \frac{1188}{1485} = \frac{1188 \div 9}{1485 \div 9} = \frac{132}{165} = \frac{132 \div 33}{165 \div 33} = \frac{4}{5} \)

Ответ: 4) 5/12, 37/333, 1/3, 7/8, 11/13, 7/9, 4/5, 11/13, 17/19, 5/6, 4/5. 5) 2/3, 40/127, 5/9, 9/13, 14/17, 4/5.