Answer: 7 large dogs
Step-by-step explanation
2 hrs = 2*60 = 120 mins
Maria needs 16 minutes for each large dog. Having a total of 120 minutes will mean she can walk up to 7 large dogs because 120/16 = 7.5 and that rounds down to 7.
- 7 large dogs ---> 7*16 = 112 mins = a little under 2 hrs
- 8 large dogs ---> 8*16 = 128 mins = a little over 2 hrs
Side note: This assumes that Maria walks one dog at a time.