Завдання 1201 - 1300 » 1219

Виконай дії: 1) –7/18 · 14/7 – (–4/21) · (–11/6) = – (7 ∙ 11)/(18 ∙ 7) – (4 ∙ 7)/(21 ∙ 6) = – 11/18 + (–2/9) = – (11 + 4)/18 = – 15/18 = –5/6; 2) (17/8 · (–14/5) + 9/16) · (–8/9); 1) 17/8 · (–14/5) = – (15 ∙ 9)/(8 ∙ 5) = – 27/8 = –33/8; 2) –33/8 + 9/16 = –(211/8 – 9/16) = –2(22 - 9)/16 = –213/16; 3) –213/16 · (–8/9) = (45 ∙ 8)/(16 ∙ 9) = 5/2 = 21/2; 3) (–19/25 + 0,4 · (–3/5)) · 0,8 = (–0,76 + 0,4 · (–0,6)) · 0,8 = (–0,76 + + (–0,24)) · 0,8 = –1 · 0,8 = –0,8; 4) –9,6 · 5/16 + 9,06 – (–3,4)2= – (96 ∙ 5)/(10 ∙ 16) + 9,06 – 11,56 = –3 + 9,06 – – 11,56 = 9,06 – 14,56 = 9,06 + (–14,56) = –5,5.