Контрольные задания
Вопрос:Фото задания: 11 вар. 1) 1/4 + 3/5; 2) 13 − 3 13/25; 3) 7 1/3 + 2 18/27; 4) 9 4/21 − 4 11/14; 5) 7/15 × 45/49; 6) 3/5 × 1 3/6; 7) 6 ·…Фото задания

Ответ:

  1. \(\frac{1}{4}+\frac{3}{5}=\frac{5}{20}+\frac{12}{20}=\frac{17}{20}\).
  2. \(13-3\frac{13}{25}=12\frac{25}{25}-3\frac{13}{25}=9\frac{12}{25}\).
  3. \(7\frac{1}{3}+2\frac{18}{27}=7\frac{1}{3}+2\frac{2}{3}=10\).
  4. \(9\frac{4}{21}-4\frac{11}{14}=\frac{193}{21}-\frac{67}{14}=\frac{386-201}{42}=4\frac{17}{42}\).
  5. \(\frac{7}{15}\cdot\frac{45}{49}=\frac{3}{7}\).
  6. \(\frac{3}{5}\cdot1\frac{3}{6}=\frac{3}{5}\cdot\frac{3}{2}=\frac{9}{10}\).
  7. \(6\cdot\frac{3}{4}=\frac{18}{4}=\frac{9}{2}=4\frac{1}{2}\).
  8. \(3\frac{1}{2}:2\frac{5}{8}=\frac{7}{2}:\frac{21}{8}=\frac{7}{2}\cdot\frac{8}{21}=\frac{4}{3}=1\frac{1}{3}\).