(1 1/4 : 2 1/2 + 3 3/7 · 1 5/9) : 5/12 - 8 1/5 = 5 4/5
1) 1 1/4 : 2 1/2 = 5/4 : 5/2 = 5/4 · 2/5 = 2/4 = 1/2
2) 3 3/7 · 1 5/9 = 24/7 · 14/9 = (8·2)/(1·3) = 16/3 = 5 1/3
3) 1/2 + 5 1/3 = 3/6 + 5 2/6 = 5 5/6
4) 5 5/6 : 5/12 = 35/6 · 12/5 = (7·2)/(1·1) = 14
5) 14 - 8 1/5 = 13 5/5 - 8 1/5 = 5 4/5
ответ: 5 целых 4/5 (или 5,8 в десятичных дробях).
