5.26 Раскройте скобки и вычислите: a) 7,646 - (6,9 – 2,054); б) 4,17 + (9,182 – 4,17); 1) (\frac{3}{8}+\frac{2}{13})-(\frac{7}{8}+\frac{1}{13}); г) д) -(3,69 - 6\frac{2}{13}) - (1,31-8\frac{11}{13}); e)-(+2,43) - (-5,93-\frac{1}{4})

Ответ: а) 2,7; б) 9,182; г) -\(\frac{1}{2}\); д) 10\(\frac{10}{13}\); e) 3,68

Раскроем скобки и вычислим:

а) 7,646 - (6,9 – 2,054) = 7,646 - 6,9 + 2,054 = 0,746 + 2,054 = 2,7

б) 4,17 + (9,182 – 4,17) = 4,17 + 9,182 - 4,17 = 9,182

г) (\(\frac{3}{8}\) + \(\frac{2}{13}\)) - (\(\frac{7}{8}\) + \(\frac{1}{13}\)) = \(\frac{3}{8}\) + \(\frac{2}{13}\) - \(\frac{7}{8}\) - \(\frac{1}{13}\) = (\(\frac{3}{8}\) - \(\frac{7}{8}\)) + (\(\frac{2}{13}\) - \(\frac{1}{13}\)) = -\(\frac{4}{8}\) + \(\frac{1}{13}\) = -\(\frac{1}{2}\) + \(\frac{1}{13}\) = -\(\frac{13}{26}\) + \(\frac{2}{26}\) = -\(\frac{11}{26}\)

д) -(3,69 - 6\(\frac{2}{13}\)) - (1,31 - 8\(\frac{11}{13}\)) = -3,69 + 6\(\frac{2}{13}\) - 1,31 + 8\(\frac{11}{13}\) = (-3,69 - 1,31) + (6\(\frac{2}{13}\) + 8\(\frac{11}{13}\)) = -5 + 14\(\frac{13}{13}\) = -5 + 15 = 10

e) - (\(\frac{5}{8}\) + 2,43) - (-5,93 - \(\frac{1}{4}\)) = -\(\frac{5}{8}\) - 2,43 + 5,93 + \(\frac{1}{4}\) = -0,625 - 2,43 + 5,93 + 0,25 = -3,055 + 6,18 = 3,125

Ответ: а) 2,7; б) 9,182; г) -\(\frac{1}{2}\); д) 10\(\frac{10}{13}\); e) 3,68