Question

Вариант 4, первое, математика, 10 баллов

Answer 1

$24\dfrac{7}{9} + 23\dfrac{1}{9} = (24 + \dfrac{7}{9}) + (23 + \dfrac{1}{9}) = (24 + 23) + (\dfrac{7}{9} + \dfrac{1}{9}) = 47 + \dfrac{8}{9} = 47\dfrac{8}{9}$

$24\dfrac{7}{9} + 17 = (24 + \dfrac{7}{9}) + 17 = (24 + 17) + \dfrac{7}{9} = 41 + \dfrac{7}{9} = 41\dfrac{7}{9}$

$24\dfrac{7}{9} + \dfrac{2}{9} = (24 + \dfrac{7}{9}) + \dfrac{2}{9} = 24 + (\dfrac{7}{9} + \dfrac{2}{9}) = 24 + \dfrac{9}{9} = 24 + 1 = 25$

$50\dfrac{5}{8} - 50 = (50 + \dfrac{5}{8}) - 50 = (50 - 50) + \dfrac{5}{8} = 0 + \dfrac{5}{8} = \dfrac{5}{8}$

$50\dfrac{5}{8} - 25 = (50 + \dfrac{5}{8}) - 25 = (50 - 25) + \dfrac{5}{8} = 25 + \dfrac{5}{8} = 25\dfrac{5}{8}$

$50\dfrac{5}{8} - \dfrac{5}{8} = (50 + \dfrac{5}{8}) - \dfrac{5}{8} = 50 + (\dfrac{5}{8} - \dfrac{5}{8}) = 50 + 0 = 50$

$50\dfrac{5}{8} - 50\dfrac{3}{8} = (50 + \dfrac{5}{8}) - (50 + \dfrac{3}{8}) = (50 - 50) + (\dfrac{5}{8} - \dfrac{3}{8}) = 0 + \dfrac{2}{8} = \dfrac{2}{8} = \dfrac{1}{4}$