Miles driven for each trip are different

I fostered dogs during 2016.  I did different trips around the area to take them to vetting, adoption events, stores, etc.  When I tried to enter these into the mileage area the program is asking me to enter the number of trips per year and the miles driven for each trip.  How can I enter this?  some trips were 10 miles but others were 200 miles.  I thought I could enter the total of all the miles that I drove around.