Завдання 1301 - 1401 » 1378

Обчисліть: 1) (–7,7 – 7,3) ∙ (–7/25 : (–6,3) + (–2,6) : 14/5) = –15 ∙ (7/25 ∙ 10/63 – 13/5 ∙ 5/9) = –15 ∙ (2/45 – 13/9) = –15 ∙ (–63/45) = 21; 2) (3/5 + 5,6 : 1,4) : (–1/7 ∙ (–2,1) + (–1,5) : (–0,75)) = (3/5 + 4) : (1/7 ∙ 21/10 + 2) = 23/5 : 23/10 = 23/5 ∙ 10/23 = 2; 3) –3,2 : (–0,8) + (–1,4) : 1/2 : (1 – 3/10 : (–1,8)) = 4 – 7/5 ∙ 2 : (1 + 3/10 ∙ 5/9) = 4 – 7/5 ∙ 2 : (1 + 1/6) = 4 – 7/5 ∙ 2 ∙ 6/7 = 4 – 12/5 = 8/5 = 13/5.