11. Раціональні числа - 14. Віднімання чисел » 528
Обчисли значення виразу. а) –21/3 + (–31/6 + 1/2) = –22/6 + (–27/6 + 3/6) = –22/6 + –24/6 = –46/6 = –5; б) –2/15 + (52/3 + (–0,5)) + (–0,7 + (–11/3)) = –2/15 + (52/3 + (–1/2)) + (–7/10 + (–11/3)) = –2/15 + (54/6 + (–3/6)) + (–21/30 + (–110/30)) = –2/15 + 51/6 + (–131/30) = –4/30 + 435/30 + (–131/30) = 435/30 + (–135/30) = 3; в) (–1/12 + 7/9 + (–3/4)) + (–1/3 + 17/18) = (–3/36 + 28/36 + (–27/36)) + (–12/36 + 114/36) = –2/36 + 12/36 = 1; г) (–11/6 + 0,15) + (–3,35 + (–3/5)) + 4/15 = (–11/6 + 3/20) + (–37/20 + (–3/5)) + 4/15 = (–110/60 + 9/60) + (–321/60 + (–36/60)) + 16/60 = –11/60 + (–357/60) + 16/60 = –458/60 + 16/60 = –442/60 = –47/10.