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Чому дорівнює значення виразу: 1) 185/12 – 7/12 ∙ 119/21 – 17/72 ∙ 2/3 = 185/12 – 7/12 ∙ 40/21 – 17/72 ∙ 2/3 = 185/12 = (1 • 10)/(3 • 3) – (17 • 1)/(36 • 3) = 185^(\9)/12 – 11^12/9 – 17/108 = 17(45 - 12 - 17)/108 = 1716/108 = 174/27; 2) (63/4 – 51/8 : 19/32) ∙ 5/11 = (63/4 – 41/8 : 41/32) ∙ 5/11 = (63/4 – 41/8 ∙ 32/41) ∙ 5/11 = = (63/4 – 4) ∙ 5/11 = 23/4 ∙ 5/11 = 11/4 ∙ 5/11 = 11/4; 3) (–1,42 – (–3,22)): (–0,4) + (–6) ∙ (–0,7) = (–1,42 + 3,22) : (–0,4) + 4,2 = 1,8 : (–0,4) + 4,2 = –4,5 + 4,2 = –0,3; 4) (–7^(\2)/18 + 11^(\3)/12) : (–19/48) = – (-14+33)/36 ∙ 48/19 = – (19 • 48)/(36 • 19) = – 4/3 = –11/3; 5) (–31^(\5)/12 – 21^(\4)/15) : (–53/20) = –5(5+4)/60 : (–103/20) = 59/60 ∙ 20/103 = (309 • 20)/(60 • 103) = 1.