(7/10 + 3/15 ) × 2 14/23 + 1 6/57 : (7/19 -30/57) =
= 9/10 ×60/23 + 63/57 : (- 9/57) =
= 54/23 + (-7) = - 4 15/23
Можно по действиям:
1)7/10+3/15= 21/30 + 6/30 =27/30 = 9/10
2) 7/19 - 30/57 = 21/57 - 30/57 = - 9/57 =-3/19
3) 9/10 × 2 14/23= 9/10 × 60/23 = (9×6) / (1×23) =54/23= 2 8/23
4) 63/57 : (-3/19 ) =63/57 × (-19/3) = - (63×19)/(57×3) = -7
5) 2 8/23 + (-7) = - 4 15/23