I need an answer for this

3) 225 / 250 + 225 + 275
225 / 750
4) 1 - (20 / 20 + 30 + 15 + 25)
1 - ( 20 / 90)
1 - 2/9 =
or
30 + 15 + 15 / 20 + 30 + 15 + 25
70 / 90