1. б) Вычислите: 1 1/4 + 5/17 · 2 4/15 : 2 1/8 : 51/56

1 1/4 + 5/17 · 2 4/15 : 2 1/8 : 51/56 = 5/4 + 5/17 · 34/15 · 17/16 · 56/51 = 5/4 + (5·34·17·56)/(17·15·16·51) = 5/4 + (5·2·17·56)/(15·16·51) = 5/4 + (1·2·17·56)/(3·16·51) = 5/4 + (2·17·56)/(3·16·51) = 5/4 + (17·56)/(3·8·51) = 5/4 + (17·7)/(3·1·51) = 5/4 + 119/153 = 5/4 + 7/9 = (45+28)/36 = 73/36 = 2 1/36