Calculating and average drive time within a service area

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#1

Hi, I'm trying to calculate an average drive time within a service area. Essentially my goal is to use 50-100+ points within a service area and calculate the average drive time to a specific point of interest.
Ideally I would be able to run a model that chooses different points each time to come up with a more accurate average. Is this possible?

Point of interest: 2412 50th St Lubbock, 79412

Service area Zip Codes:
Primary Service area-
79412
79423
79424
79413
79403
79416
79414
79404
79407
79415
79411

Secondary service area
79364
79336
88101
79382
79410
79401
79549
79072
79331
79316
79363
88240
88220
79311