There are 1 x 60 minutes = <<1*60=60>>60 minutes in 1 hour.
There are 60/5 = <<60/5=12>>12 sets of 5 minutes in 1 hour.
So, Jane can fold 3 x 12 = <<3*12=36>>36 towels in an hour.
There are 60/10 = <<60/10=6>>6 sets of 10 minutes in 1 hour.
So, Kyla can fold 5 x 6 = <<5*6=30>>30 towels in an hour.
There are 60/20 = <<60/20=3>>3 sets of 20 minutes in 1 hour.
So, Anthony can fold 7 x 3 = <<7*3=21>>21 towels in an hour.
Therefore, the 3 of them can fold a total of 36 + 30 + 21 = <<36+30+21=87>>87 towels in 1 hour.
#### 87