A few days ago when I was driving, I noticed my car's odometer was about to hit 99,900 miles (my odometer ONLY shows an integer, no decimal points; while my trip meter always gives 1 decimal point). So I asked myself, at some points of time in the future, if I wanted to be able to take two pictures where on picture 1) I have number "99.9" on my trip mater, 99,999 on my odometer and on picture 2) I have number "100.0" on my trip mater, and 100,000 on my odometer. Then, when, in terms of my odometer's millage number, should I start resetting my trip meter?
I am expecting to see a "range" as the answer but I haven't been able to completely figure out. Just to demonstrate the idea, for example, if I reset my trip meter when my odometer JUST hit 99,900, then I can achieve my goals: because after I drive another 99.9 miles, I can get picture 1); then after I drive another 0.1 miles, I can get picture 2).
Another example, if I reset my trip meter RIGHT AFTER my odometer hit 99899.9, aka >99899.9, then I can achieve my goals too. Because after I drive another 99.9 miles, I can get picture 1 (because my trip meter will show 99.9 and odometer will show [99899.9 + 99.9] = 99999); then RIGHT BEFORE my trip meter is about to hit 100.1, aka. <100.1, there is a chance my odometer would turn 100,000.
Here let's assume car's odometer always underestimates the actual distance. i.e. when you see 103 on your odometer, you definitely have driven >= 103 miles.
Thanks a lot!