First find how long half Jake's dad's trip is: 30 minutes / 2 = <<30/2=15>>15 minutes
Then convert the minutes to hours: 15 minutes * 1 hour/60 minutes = .25 hours
Now find how far Jake's dad travels at 28 miles per hour: .25 hours * 28 miles per hour = <<.25*28=7>>7 miles
Then find how far Jake's dad travels at 60 miles per hour: .25 hours * 60 miles per hour = <<.25*60=15>>15 miles
Now add those distances to find the total distance to the water park: 7 miles + 15 miles = <<7+15=22>>22 miles
Now divide the total distance by Jake's speed to find how long it takes him: 22 miles / 11 miles/hour = <<22/11=2>>2 hours
#### 2