Hi sheltongrant1991!
From time of mailing, the standard for the postal service is two weeks. However geographic location does play a factor. Meaning if you are one state away from Pennsylvania (which is where Penn Foster's headquarters are located), then it most likely will take less time to get to you than someone who lives in Seattle Washington. Once your proctor receives the exam(s), you will have 3 weeks to complete them.
Hope this makes sense! Good luck on your exams!!