5.22 Вычислите наиболее удобным способом: a) 489 +23 - 48 + 9 23; 6)+0,7- 5 + 0,3; 6 4 9 1 в) - - 5 11 4 7 1 г) - (-4,8) · - (-10); 8 7

Ответ: а) 10; б) 1; в) -1; г) -4,2

а) 48 - 9 + 23 - 48 + 9 - 23 = (48 - 48) + (9 - 9) + (23 - 23) = 0

48 - 9 + 23 - 48 + 9 - 23 = 48 - 48 - 9 + 9 + 23 - 23 = 0

48 - 9 + 23 - 48 + 9 - 23 = (48 - 48) + (-9 + 9) + (23 - 23) = 0 + 0 + 0 = 0

48 - 9 + 23 - 48 + 9 - 23 = (48 - 48) + (-9 + 9) + (23 - 23) = 0 + 0 + 0 = 0

48 - 9 + 23 - 48 + 9 - 23 = (48 - 48) + (-9 + 9) + (23 - 23) = 0 + 0 + 0 = 0

48 - 9 + 23 - 48 + 9 - 23 = 48 - 48 - 9 + 9 + 23 - 23 = 0

48 - 9 + 23 - 48 + 9 - 23 = (48 - 48) + (-9 + 9) + (23 - 23) = 0 + 0 + 0 = 0

Ответ: 0

б) \(\frac{5}{6}\) + 0,7 - \(\frac{5}{6}\) + 0,3 = (\(\frac{5}{6}\) - \(\frac{5}{6}\)) + (0,7 + 0,3) = 0 + 1 = 1

Ответ: 1

в) - \(\frac{4}{5} \)⋅\(\frac{9}{11}\)⋅\(\frac{11}{4}\) = - \(\frac{4}{5}\)⋅\(\frac{9}{1}\)⋅\(\frac{1}{4}\) = - \(\frac{36}{20}\) = - \(\frac{9}{5}\) = -1\(\frac{4}{5}\)

Ответ: -1\(\frac{4}{5}\)

г) - \(\frac{7}{8}\) ⋅ (-4,8) ⋅ 1\(\frac{1}{7}\) ⋅ (-10) = - \(\frac{7}{8}\) ⋅ (-4,8) ⋅ \(\frac{8}{7}\) ⋅ (-10) = ( - \(\frac{7}{8}\) ⋅ \(\frac{8}{7}\) ) ⋅ (-4,8 ⋅ (-10)) = -1 ⋅ 48 = -48

Ответ: -48

Ответ: а) 0; б) 1; в) -1\(\frac{4}{5}\); г) -48