Вычислите : 1 - 4/7 ; 1 - 7/8 ; 1 - 2/9 ; 1 - 3/4 ; 3 - 1/2 ; 2 - 3/4 ; 1 - 4/15 ; 1 - 3/7 . Это дроби

Большое спасибо

1 - 4/7 = 7/7 - 4/7 = 3/7 ; 1 - 7/8 = 8/8 - 7/8 = 1/8 ; 1 - 2/9 = 9/9 - 2/9 = 7/9; 1 - 3/4 = 4/4 - 3/4 = 1/4; 3 - 1/2 = 2 2/2 - 1/2 = 2 1/2 ; 2 - 3/4 = 1 4/4 - 3/4 = 1 1/4; 1 - 4/15 =15/15 - 4/15 = 11/15; 1 - 3/7 = 7/7 - 3/7 = 4/7.