8 – 4,2 / ( 25/14 -1 4/21)

Question

8 – 4,2 / ( 25/14 -1 4/21)

Answer 1

1)25/14-1 4/21=25/14-25/21=25/42

2)4,2:25/42=21/5:25/42=21/45*42/25=98/125

3)8-98/125=7 27/125