Given parameters: 
Distance covered by Raina = 7 miles 
Time taken = 50 minutes
Unknown: 
Distance covered in 75 minutes = ? 
To solve this problem, we have to find the speed of Raina during the first 50 minutes. 
 Speed is the distance covered with time. 
 Speed = 
 
 
 Input the parameters and solve; 
 Speed = 
 = 0.14miles/min
 = 0.14miles/min
Now, to find the distance covered in the second run; 
 Distance = speed x time taken
 = 0.14miles/min x 75min 
 = 10.5miles
The distance covered in miles is 10.5miles