(1 3/5 + 2 1/5) ÷ 1 9/10 + (1 7/10 - 4/5) ÷ 3/7= (8/5 + 11/5) ÷ 19/10 + (7/10 - 4/5) ÷ 3/7= 19/5 ÷ 19/10 + (7/10 - 4/5) ÷ 3/7= 19/5 10/19 + (7/10 - 4/5) 7/3= 2 + (7/10 - 4/5) 7/3= 2 + (7/10 - 8/10) 7/3= 2 + (-1/10) * 7/3= 2 + (-7/30)= 2 - 7/30= 60/30 - 7/30= 53/30
Ответ: 53/30
(1 3/5 + 2 1/5) ÷ 1 9/10 + (1 7/10 - 4/5) ÷ 3/7
= (8/5 + 11/5) ÷ 19/10 + (7/10 - 4/5) ÷ 3/7
= 19/5 ÷ 19/10 + (7/10 - 4/5) ÷ 3/7
= 19/5 10/19 + (7/10 - 4/5) 7/3
= 2 + (7/10 - 4/5) 7/3
= 2 + (7/10 - 8/10) 7/3
= 2 + (-1/10) * 7/3
= 2 + (-7/30)
= 2 - 7/30
= 60/30 - 7/30
= 53/30
Ответ: 53/30