Answer:
50 Days
Explanation:
To figure out how often Sara walks her dog in the 60 day period divide 60 by 3. Sara
To figure out how often Marsha walks her dog in the 60 day period divide 60 by 2. Marsha walked her dog for 30 days out of the 60 day period
To find out how many days combined, add 20 and 30 to get 50 Days