For the box with a capacity of 80, if it was 3/4 full with oranges, it had 3/4*80 = <<80*3/4=60>>60 oranges.
The second box, with a capacity of 50, was 3/5 full with oranges, which totals 3/5*50 = <<3/5*50=30>>30 oranges.
Together, the two boxes have 60+30 = <<60+30=90>>90 oranges
#### 90