Решить. это дроби. 7 10/15 - (3 9/20 + 1 1/30) =

7 10/15 - (3 9/20 + 1 1/30) = 2 11/15.

1) 3 9/20 + 1 1/30= 3 27/60 + 1 2/60 = 4+28/30= 4 28/30= 4 14/15.
2) 7 10/15 - 4 14/15= 6 25/15 - 4 14/15 = 2+ 11/15= 2 11/15.