A) ( x - 3/8 ) * 8/35 + 2 2/7 = 2 2/5
( x - 3/8 ) * 8/35 + 16/7 =12/5 умножим на 35
( x - 3/8 ) * 8 + 16*5 =12*7
8х-3+80=84
8х=84-80+1
8х=5
х=5/8=0,625
б) 5 5/7 + ( x - 2 3/7 ) = 8 2/7
5 5/7 + x - 2 3/7 = 8 2/7
х+3 2/7=8 2/7
х=8 2/7-3 2/7=6
в) 6 1/5 - ( 2 3/5 + x ) = 3 2/5
6 1/5 - 2 3/5 - x = 3 2/5
6 1/5 - 2 3/5 - x = 3 2/5
4 1/5- 3/5-х= 3 2/5
4 - 2/5-х= 3 2/5
3 3/5-х= 3 2/5
х=3 3/5- 3 2/5=1/5=0,2